<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e6946-f36d-7779-bc3c-cd1ae693477d,g:7c8e9d25-f064-4b1c-b265-17ca047fd591-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.morganstanley.com/role/CoverPage" xlink:type="simple" xlink:href="ms-20260630.xsd#CoverPage"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/CoverPage" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_019e6946-fec9-7bbc-b8cc-baae27016f9a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentInformationTable_019e6946-fec9-7bbc-b8cc-baae27016f9a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e6946-fec9-7e12-9116-3d258abed270" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_019e6946-fec9-7bbc-b8cc-baae27016f9a" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e6946-fec9-7e12-9116-3d258abed270" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-7e12-9116-3d258abed270_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e6946-fec9-7e12-9116-3d258abed270" xlink:to="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-7e12-9116-3d258abed270_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e6946-fec9-7e12-9116-3d258abed270" xlink:to="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019e6946-fec9-7c1e-9fe0-0e7f3d17c350" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_us-gaap_CommonClassAMember_019e6946-fec9-7c1e-9fe0-0e7f3d17c350" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_019e6946-fec9-7cee-9996-7c8d280a686e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesAPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_019e6946-fec9-7cee-9996-7c8d280a686e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesEPreferredStockMember_019e6946-fec9-7119-96df-2012632b40c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesEPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_us-gaap_SeriesEPreferredStockMember_019e6946-fec9-7119-96df-2012632b40c2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesFPreferredStockMember_019e6946-fec9-7a14-a64c-28137c4b6046" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesFPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_us-gaap_SeriesFPreferredStockMember_019e6946-fec9-7a14-a64c-28137c4b6046" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesIPreferredStockMember_019e6946-fec9-783d-960b-c3032be5ccf4" xlink:href="ms-20260630.xsd#ms_SeriesIPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_SeriesIPreferredStockMember_019e6946-fec9-783d-960b-c3032be5ccf4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesKPreferredStockMember_019e6946-fec9-7169-a2df-428977be60a0" xlink:href="ms-20260630.xsd#ms_SeriesKPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_SeriesKPreferredStockMember_019e6946-fec9-7169-a2df-428977be60a0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesLPreferredStockMember_019e6946-fec9-7434-b3f6-7d7b962d6239" xlink:href="ms-20260630.xsd#ms_SeriesLPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_SeriesLPreferredStockMember_019e6946-fec9-7434-b3f6-7d7b962d6239" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesOPreferredStockMember_019e6946-fec9-7266-983c-a48ac66018d6" xlink:href="ms-20260630.xsd#ms_SeriesOPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_SeriesOPreferredStockMember_019e6946-fec9-7266-983c-a48ac66018d6" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesPPreferredStockMember_019e6946-fec9-7551-9914-30c305a3b160" xlink:href="ms-20260630.xsd#ms_SeriesPPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_SeriesPPreferredStockMember_019e6946-fec9-7551-9914-30c305a3b160" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesQPreferredStockMember_019e6946-fec9-7bd3-97bb-916941a77fa6" xlink:href="ms-20260630.xsd#ms_SeriesQPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_SeriesQPreferredStockMember_019e6946-fec9-7bd3-97bb-916941a77fa6" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_GlobalMediumTermNotesSeriesAFloatingRateNotesDue2029OfMorganStanleyFinanceLLCMember_019e6946-fec9-7921-b5ff-26fe93fac10d" xlink:href="ms-20260630.xsd#ms_GlobalMediumTermNotesSeriesAFloatingRateNotesDue2029OfMorganStanleyFinanceLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6946-fec9-70a5-826b-a8657bb2ac88" xlink:to="loc_ms_GlobalMediumTermNotesSeriesAFloatingRateNotesDue2029OfMorganStanleyFinanceLLCMember_019e6946-fec9-7921-b5ff-26fe93fac10d" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019e6946-fec9-74a2-8bdf-245d57ff4afe" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentType_019e6946-fec9-74a2-8bdf-245d57ff4afe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019e6946-fec9-7fa4-a082-d381cd065ead" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentPeriodEndDate_019e6946-fec9-7fa4-a082-d381cd065ead" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019e6946-fec9-76a6-b507-22ecc6da03c2" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityFileNumber_019e6946-fec9-76a6-b507-22ecc6da03c2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019e6946-fec9-7cbd-b4ba-1f9804dce780" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityRegistrantName_019e6946-fec9-7cbd-b4ba-1f9804dce780" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019e6946-fec9-7d72-93b2-79858de6c8eb" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019e6946-fec9-7d72-93b2-79858de6c8eb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019e6946-fec9-770d-9677-595a1d5b222e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityAddressAddressLine1_019e6946-fec9-770d-9677-595a1d5b222e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019e6946-fec9-7737-ad2c-4a0d8391e227" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityAddressCityOrTown_019e6946-fec9-7737-ad2c-4a0d8391e227" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019e6946-fec9-72f8-a979-004e6e34a8a0" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityAddressStateOrProvince_019e6946-fec9-72f8-a979-004e6e34a8a0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019e6946-fec9-7d4b-9921-19270746bf38" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityAddressPostalZipCode_019e6946-fec9-7d4b-9921-19270746bf38" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019e6946-fec9-764f-951c-39506d289687" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityTaxIdentificationNumber_019e6946-fec9-764f-951c-39506d289687" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019e6946-fec9-7bf0-9266-b606433a01de" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_CityAreaCode_019e6946-fec9-7bf0-9266-b606433a01de" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019e6946-fec9-7d2d-b293-ec78a140673a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_LocalPhoneNumber_019e6946-fec9-7d2d-b293-ec78a140673a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019e6946-fec9-701b-83f8-e530f11630c0" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_Security12bTitle_019e6946-fec9-701b-83f8-e530f11630c0" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019e6946-fec9-7b72-a924-ba2feaf5de8a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_TradingSymbol_019e6946-fec9-7b72-a924-ba2feaf5de8a" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019e6946-fec9-76be-b1b8-4750d4162932" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_SecurityExchangeName_019e6946-fec9-76be-b1b8-4750d4162932" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCurrentReportingStatus_019e6946-fec9-7227-b146-14a00de747de" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCurrentReportingStatus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityCurrentReportingStatus_019e6946-fec9-7227-b146-14a00de747de" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInteractiveDataCurrent_019e6946-fec9-7527-a99e-aa69ffd5e247" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityInteractiveDataCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityInteractiveDataCurrent_019e6946-fec9-7527-a99e-aa69ffd5e247" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFilerCategory_019e6946-fec9-7532-b56d-07e8abc35aa3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFilerCategory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityFilerCategory_019e6946-fec9-7532-b56d-07e8abc35aa3" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness_019e6946-fec9-7377-8aaf-ed580f03c174" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntitySmallBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntitySmallBusiness_019e6946-fec9-7377-8aaf-ed580f03c174" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019e6946-fec9-727f-8196-ee8fc4d6c3a8" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityEmergingGrowthCompany_019e6946-fec9-727f-8196-ee8fc4d6c3a8" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityShellCompany_019e6946-fec9-77f0-afdf-fa2fa5d71b04" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityShellCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityShellCompany_019e6946-fec9-77f0-afdf-fa2fa5d71b04" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_019e6946-fec9-702e-93f8-87c36270cd4b" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_019e6946-fec9-702e-93f8-87c36270cd4b" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019e6946-fec9-7f23-88bd-b128039be99e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_AmendmentFlag_019e6946-fec9-7f23-88bd-b128039be99e" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalYearFocus_019e6946-fec9-7ae4-a6f8-b4650f20135b" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentFiscalYearFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentFiscalYearFocus_019e6946-fec9-7ae4-a6f8-b4650f20135b" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalPeriodFocus_019e6946-fec9-7e88-a990-0eb54c41d28a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentFiscalPeriodFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentFiscalPeriodFocus_019e6946-fec9-7e88-a990-0eb54c41d28a" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019e6946-fec9-7a16-b794-07d913ed6791" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_EntityCentralIndexKey_019e6946-fec9-7a16-b794-07d913ed6791" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate_019e6946-fec9-779b-9037-252fd6ab8aa6" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_CurrentFiscalYearEndDate_019e6946-fec9-779b-9037-252fd6ab8aa6" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentQuarterlyReport_019e6946-fec9-75de-a02a-77cd1dadfb63" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentQuarterlyReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentQuarterlyReport_019e6946-fec9-75de-a02a-77cd1dadfb63" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentTransitionReport_019e6946-fec9-7b92-9d2d-68cb90feeb4a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentTransitionReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_dei_DocumentTransitionReport_019e6946-fec9-7b92-9d2d-68cb90feeb4a" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_019e6946-fec9-709e-b783-de46516a2711" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e6946-fec9-76fb-8321-4511dc0c0af4" xlink:to="loc_us-gaap_NumberOfReportableSegments_019e6946-fec9-709e-b783-de46516a2711" xlink:type="arc" order="29"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/ConsolidatedStatementofChangesinTotalEquityUnaudited" xlink:type="simple" xlink:href="ms-20260630.xsd#ConsolidatedStatementofChangesinTotalEquityUnaudited"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/ConsolidatedStatementofChangesinTotalEquityUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e6946-fec9-721f-9a2b-0c58d34a1aea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e6946-fec9-7a73-aa4f-ef4befdfad45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e6946-fec9-721f-9a2b-0c58d34a1aea" xlink:to="loc_us-gaap_StatementTable_019e6946-fec9-7a73-aa4f-ef4befdfad45" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e6946-fec9-7cb0-a7b5-d09522167b84" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e6946-fec9-7a73-aa4f-ef4befdfad45" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e6946-fec9-7cb0-a7b5-d09522167b84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7cb0-a7b5-d09522167b84_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6946-fec9-7cb0-a7b5-d09522167b84" xlink:to="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7cb0-a7b5-d09522167b84_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6946-fec9-7cb0-a7b5-d09522167b84" xlink:to="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockMember_019e6946-fec9-77ec-8256-a4e4ae8cc5a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_PreferredStockMember_019e6946-fec9-77ec-8256-a4e4ae8cc5a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019e6946-fec9-71e4-9ca4-dccfd9d05e54" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_CommonStockMember_019e6946-fec9-71e4-9ca4-dccfd9d05e54" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019e6946-fec9-74c7-86eb-a78deb94abae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019e6946-fec9-74c7-86eb-a78deb94abae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019e6946-fec9-73c9-98dd-31df81b5e4b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_RetainedEarningsMember_019e6946-fec9-73c9-98dd-31df81b5e4b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrustForBenefitOfEmployeesMember_019e6946-fec9-794e-9072-44a1f753ea22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TrustForBenefitOfEmployeesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_TrustForBenefitOfEmployeesMember_019e6946-fec9-794e-9072-44a1f753ea22" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6946-fec9-76fc-996d-345c2592cced" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6946-fec9-76fc-996d-345c2592cced" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_019e6946-fec9-70c7-900a-e8346091e8ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_TreasuryStockCommonMember_019e6946-fec9-70c7-900a-e8346091e8ca" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommonStockIssuedToEmployeeTrustMember_019e6946-fec9-75ca-8d7c-3617973b7195" xlink:href="ms-20260630.xsd#ms_CommonStockIssuedToEmployeeTrustMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_ms_CommonStockIssuedToEmployeeTrustMember_019e6946-fec9-75ca-8d7c-3617973b7195" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_019e6946-fec9-7b1a-be3c-5962a653c782" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6946-fec9-7444-b973-ccde7269544a" xlink:to="loc_us-gaap_NoncontrollingInterestMember_019e6946-fec9-7b1a-be3c-5962a653c782" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e6946-fec9-721f-9a2b-0c58d34a1aea" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e6946-fec9-77ff-b35f-2d9165a6b0d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e6946-fec9-77ff-b35f-2d9165a6b0d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_019e6946-fec9-7857-a7c4-c6a1d3de4848" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_019e6946-fec9-7857-a7c4-c6a1d3de4848" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e6946-fec9-70d9-9032-4ea1ed738f56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_NetIncomeLoss_019e6946-fec9-70d9-9032-4ea1ed738f56" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPreferredStock_019e6946-fec9-79e7-901f-e49ac8b0ccce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsPreferredStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_DividendsPreferredStock_019e6946-fec9-79e7-901f-e49ac8b0ccce" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_019e6946-fec9-76f4-be14-b3f243d28fc2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_DividendsCommonStock_019e6946-fec9-76f4-be14-b3f243d28fc2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOther_019e6946-fec9-772b-b1ea-a7e44935f4cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_StockholdersEquityOther_019e6946-fec9-772b-b1ea-a7e44935f4cb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e6946-fec9-7191-b10a-811293f10121" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e6946-fec9-7191-b10a-811293f10121" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TreasuryStockValueAcquiredCostMethodAndEmployeeTaxWithholdings_019e6946-fec9-7f48-8378-a6f66b12effa" xlink:href="ms-20260630.xsd#ms_TreasuryStockValueAcquiredCostMethodAndEmployeeTaxWithholdings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_ms_TreasuryStockValueAcquiredCostMethodAndEmployeeTaxWithholdings_019e6946-fec9-7f48-8378-a6f66b12effa" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNonredeemableNoncontrollingInterest_019e6946-fec9-7b75-be00-f62382206b67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNonredeemableNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6946-fec9-73d5-8b55-5b2148422740" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNonredeemableNoncontrollingInterest_019e6946-fec9-7b75-be00-f62382206b67" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e6946-fec9-7469-ad09-29b4543fabab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/RegulatoryRequirementsTables" xlink:type="simple" xlink:href="ms-20260630.xsd#RegulatoryRequirementsTables"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/RegulatoryRequirementsTables" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-716f-8f80-5677771337c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7898-90fc-80731d2b14bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-716f-8f80-5677771337c7" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7898-90fc-80731d2b14bb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019e6947-0063-7a61-93be-8bb1233601d4" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7898-90fc-80731d2b14bb" xlink:to="loc_dei_LegalEntityAxis_019e6947-0063-7a61-93be-8bb1233601d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019e6947-0063-7a61-93be-8bb1233601d4_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019e6947-0063-7a61-93be-8bb1233601d4" xlink:to="loc_dei_EntityDomain_019e6947-0063-7a61-93be-8bb1233601d4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019e6947-0063-7ed3-abb8-5554d62a2dbf" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019e6947-0063-7a61-93be-8bb1233601d4" xlink:to="loc_dei_EntityDomain_019e6947-0063-7ed3-abb8-5554d62a2dbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MorganStanleyBankNationalAssociationMember_019e6947-0063-70ef-8ce1-463fc9465947" xlink:href="ms-20260630.xsd#ms_MorganStanleyBankNationalAssociationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019e6947-0063-7ed3-abb8-5554d62a2dbf" xlink:to="loc_ms_MorganStanleyBankNationalAssociationMember_019e6947-0063-70ef-8ce1-463fc9465947" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MorganStanleyPrivateBankNationalAssociationMember_019e6947-0063-75cc-a236-aa5cca66188b" xlink:href="ms-20260630.xsd#ms_MorganStanleyPrivateBankNationalAssociationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019e6947-0063-7ed3-abb8-5554d62a2dbf" xlink:to="loc_ms_MorganStanleyPrivateBankNationalAssociationMember_019e6947-0063-75cc-a236-aa5cca66188b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MSAndCoMember_019e6947-0063-706e-bb9e-86defd71a298" xlink:href="ms-20260630.xsd#ms_MSAndCoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019e6947-0063-7ed3-abb8-5554d62a2dbf" xlink:to="loc_ms_MSAndCoMember_019e6947-0063-706e-bb9e-86defd71a298" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_019e6947-0063-7133-81e8-0f3ec7a91e16" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-716f-8f80-5677771337c7" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_019e6947-0063-7133-81e8-0f3ec7a91e16" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumFinancialRequirementsForFuturesCommissionMerchantsUnderCommodityExchangeActTextBlock_019e6947-0063-77d8-aa0e-7664b71951bf" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumFinancialRequirementsForFuturesCommissionMerchantsUnderCommodityExchangeActTextBlock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-716f-8f80-5677771337c7" xlink:to="loc_srt_MinimumFinancialRequirementsForFuturesCommissionMerchantsUnderCommodityExchangeActTextBlock_019e6947-0063-77d8-aa0e-7664b71951bf" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7d0e-ae80-b7d3b49d3231" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7d0e-ae80-b7d3b49d3231" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-748c-adac-04031dbb28e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-748c-adac-04031dbb28e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-748c-adac-04031dbb28e5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-748c-adac-04031dbb28e5" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-748c-adac-04031dbb28e5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7fcc-a60c-f3557512fbbd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-748c-adac-04031dbb28e5" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7fcc-a60c-f3557512fbbd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7dd6-9675-f0194965761f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7fcc-a60c-f3557512fbbd" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7dd6-9675-f0194965761f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7b58-b9a1-07b0c856ed56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7b58-b9a1-07b0c856ed56" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7b58-b9a1-07b0c856ed56_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7b58-b9a1-07b0c856ed56" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7b58-b9a1-07b0c856ed56_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-73fe-8580-5d6feada455e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7b58-b9a1-07b0c856ed56" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-73fe-8580-5d6feada455e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel12And3Member_019e6946-fec9-7213-aadb-aa3e8e7694fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel12And3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-73fe-8580-5d6feada455e" xlink:to="loc_us-gaap_FairValueInputsLevel12And3Member_019e6946-fec9-7213-aadb-aa3e8e7694fb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019e6946-fec9-7ef2-bab9-bec3e9a80af6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInputsLevel12And3Member_019e6946-fec9-7213-aadb-aa3e8e7694fb" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019e6946-fec9-7ef2-bab9-bec3e9a80af6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e6946-fec9-7378-9e54-2b5fbab70311" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInputsLevel12And3Member_019e6946-fec9-7213-aadb-aa3e8e7694fb" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e6946-fec9-7378-9e54-2b5fbab70311" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7c39-892b-c8a5cd80f323" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInputsLevel12And3Member_019e6946-fec9-7213-aadb-aa3e8e7694fb" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7c39-892b-c8a5cd80f323" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-704a-b759-b302839add6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-704a-b759-b302839add6d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-704a-b759-b302839add6d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-704a-b759-b302839add6d" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-704a-b759-b302839add6d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-704a-b759-b302839add6d" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-fec9-73ff-83f8-6d620be34d1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-fec9-73ff-83f8-6d620be34d1a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-7071-96bf-9f5c506cd287" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-7071-96bf-9f5c506cd287" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-fec9-7218-b622-ee975f9a1c4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-fec9-7218-b622-ee975f9a1c4c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-fec9-712d-bb94-0fa332161171" xlink:href="ms-20260630.xsd#ms_MortgageAndAssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-fec9-712d-bb94-0fa332161171" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-7e7d-aec7-bf8a096a2c28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorDebtObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-7e7d-aec7-bf8a096a2c28" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-74ba-8940-82740e18fcd5" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-74ba-8940-82740e18fcd5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateEquitiesMember_019e6946-fec9-7bd6-ab8b-1394efd494e8" xlink:href="ms-20260630.xsd#ms_CorporateEquitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d31-bc20-16785d3686e2" xlink:to="loc_ms_CorporateEquitiesMember_019e6946-fec9-7bd6-ab8b-1394efd494e8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-79a8-b49c-040e0457c0f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByLiabilityClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-79a8-b49c-040e0457c0f8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-79a8-b49c-040e0457c0f8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-79a8-b49c-040e0457c0f8" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-79a8-b49c-040e0457c0f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-77bc-af55-2d7679c2ae0f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-79a8-b49c-040e0457c0f8" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-77bc-af55-2d7679c2ae0f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-fec9-7c95-81d4-56b48f713ebd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-77bc-af55-2d7679c2ae0f" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-fec9-7c95-81d4-56b48f713ebd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-79de-af2f-f4ee0ab5bb25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-77bc-af55-2d7679c2ae0f" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-79de-af2f-f4ee0ab5bb25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-7de1-8da3-5cc071e42b63" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-77bc-af55-2d7679c2ae0f" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-7de1-8da3-5cc071e42b63" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateEquitiesMember_019e6946-fec9-719f-9c0f-6ce80c4662d7" xlink:href="ms-20260630.xsd#ms_CorporateEquitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-77bc-af55-2d7679c2ae0f" xlink:to="loc_ms_CorporateEquitiesMember_019e6946-fec9-719f-9c0f-6ce80c4662d7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7fac-bffa-20a02ba20e25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7e4a-98bb-eac759f2c3c6" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7fac-bffa-20a02ba20e25" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7fac-bffa-20a02ba20e25_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7fac-bffa-20a02ba20e25" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7fac-bffa-20a02ba20e25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7fac-bffa-20a02ba20e25" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7d37-a4d9-acc0fee16daa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7d37-a4d9-acc0fee16daa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-7875-9a50-818bd857df27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-7875-9a50-818bd857df27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-774b-adb8-000be8c5f7ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-774b-adb8-000be8c5f7ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7b3d-8f37-665067cceff8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7b3d-8f37-665067cceff8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-795b-a6a2-4701ce1bdd6a" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-72dc-9b3c-8911380e9294" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-795b-a6a2-4701ce1bdd6a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7d0e-ae80-b7d3b49d3231" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_019e6946-fec9-7e2e-a7c8-56e41be2a9f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_TradingSecuritiesDebt_019e6946-fec9-7e2e-a7c8-56e41be2a9f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNi_019e6946-fec9-7f78-a814-fee79f6707eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNi"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_EquitySecuritiesFvNi_019e6946-fec9-7f78-a814-fee79f6707eb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019e6946-fec9-71ec-8243-09b14502a3ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_DerivativeAssets_019e6946-fec9-71ec-8243-09b14502a3ac" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset_019e6946-fec9-7ce3-8870-e30e2a8737f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset_019e6946-fec9-7ce3-8870-e30e2a8737f4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-fec9-7dbd-8578-9b8daebc6fb3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-fec9-7dbd-8578-9b8daebc6fb3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInPhysicalCommoditiesFairValueDisclosure_019e6946-fec9-7af5-bd55-13e69245bde2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInPhysicalCommoditiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_InvestmentInPhysicalCommoditiesFairValueDisclosure_019e6946-fec9-7af5-bd55-13e69245bde2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TradingAssetsFairValueDisclosure_019e6946-fec9-70b9-a7bf-9b5303186d5e" xlink:href="ms-20260630.xsd#ms_TradingAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_ms_TradingAssetsFairValueDisclosure_019e6946-fec9-70b9-a7bf-9b5303186d5e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e6946-fec9-770c-875a-7acfdc02ca51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e6946-fec9-770c-875a-7acfdc02ca51" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure_019e6946-fec9-7f3b-8d9d-e62903f01948" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure_019e6946-fec9-7f3b-8d9d-e62903f01948" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_019e6946-fec9-7217-8a82-6edb4133e992" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7eae-bc6d-ddf444ee73d3" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_019e6946-fec9-7217-8a82-6edb4133e992" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7d0e-ae80-b7d3b49d3231" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsFairValueDisclosure_019e6946-fec9-751d-bb48-cde6bc57bdb1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_DepositsFairValueDisclosure_019e6946-fec9-751d-bb48-cde6bc57bdb1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingLiabilitiesFairValueDisclosure_019e6946-fec9-7878-9588-13098739e3d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingLiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_TradingLiabilitiesFairValueDisclosure_019e6946-fec9-7878-9588-13098739e3d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019e6946-fec9-7941-9417-349ffb11c28e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_DerivativeLiabilities_019e6946-fec9-7941-9417-349ffb11c28e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset_019e6946-fec9-7985-bca5-dfffbce933c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset_019e6946-fec9-7985-bca5-dfffbce933c4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_019e6946-fec9-7b54-8188-d22a5c4a4860" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_019e6946-fec9-7b54-8188-d22a5c4a4860" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherSecuredFinancingsFairValueDisclosure_019e6946-fec9-73c8-8bf2-5ac70a0e9f96" xlink:href="ms-20260630.xsd#ms_OtherSecuredFinancingsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_ms_OtherSecuredFinancingsFairValueDisclosure_019e6946-fec9-73c8-8bf2-5ac70a0e9f96" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_019e6946-fec9-7196-ac8f-2d6944e92596" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_DebtInstrumentFairValue_019e6946-fec9-7196-ac8f-2d6944e92596" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_019e6946-fec9-7508-8adb-6a6b4875b5df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7e47-8278-0af27e897517" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_019e6946-fec9-7508-8adb-6a6b4875b5df" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesDetailofLoansandLendingCommitmentsatFairValueDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesDetailofLoansandLendingCommitmentsatFairValueDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesDetailofLoansandLendingCommitmentsatFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-780a-91b4-bdfe152954c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7dd3-9276-e86664f20006" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-780a-91b4-bdfe152954c3" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7dd3-9276-e86664f20006" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-fec9-775c-b5fe-0efbf5216ab1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7dd3-9276-e86664f20006" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-fec9-775c-b5fe-0efbf5216ab1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-775c-b5fe-0efbf5216ab1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-fec9-775c-b5fe-0efbf5216ab1" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-775c-b5fe-0efbf5216ab1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-731c-86f6-a7bf9a3240dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-fec9-775c-b5fe-0efbf5216ab1" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-731c-86f6-a7bf9a3240dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-fec9-7787-a834-66419f30824d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-731c-86f6-a7bf9a3240dd" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-fec9-7787-a834-66419f30824d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-fec9-7019-bd09-d33733a20ff5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-731c-86f6-a7bf9a3240dd" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-fec9-7019-bd09-d33733a20ff5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-fec9-7e19-9a2b-260bbc6046b5" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-fec9-731c-86f6-a7bf9a3240dd" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-fec9-7e19-9a2b-260bbc6046b5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-765a-8509-08331b201c64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7dd3-9276-e86664f20006" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-765a-8509-08331b201c64" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-765a-8509-08331b201c64_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-765a-8509-08331b201c64" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-765a-8509-08331b201c64_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7fcb-ab58-631ae5882b4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-765a-8509-08331b201c64" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7fcb-ab58-631ae5882b4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-747e-b6cf-afabb008d529" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorDebtObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7fcb-ab58-631ae5882b4e" xlink:to="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-747e-b6cf-afabb008d529" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-778d-a229-47da0810736d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7dd3-9276-e86664f20006" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-778d-a229-47da0810736d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-778d-a229-47da0810736d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-778d-a229-47da0810736d" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-778d-a229-47da0810736d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-77b0-81f9-6705bcf7b646" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-778d-a229-47da0810736d" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-77b0-81f9-6705bcf7b646" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7662-9c39-9ec23f064b6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-77b0-81f9-6705bcf7b646" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7662-9c39-9ec23f064b6d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_019e6946-fec9-7427-8c52-8a38a2e126ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-780a-91b4-bdfe152954c3" xlink:to="loc_us-gaap_TradingSecuritiesDebt_019e6946-fec9-7427-8c52-8a38a2e126ba" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesDetailofUnsettledFairValueofFuturesContractsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesDetailofUnsettledFairValueofFuturesContractsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesDetailofUnsettledFairValueofFuturesContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7014-bc07-81b8304ceca1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-76e3-a4d2-f1b307c44e6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7014-bc07-81b8304ceca1" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-76e3-a4d2-f1b307c44e6a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-76ae-853e-c81d2da9777d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-76e3-a4d2-f1b307c44e6a" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-76ae-853e-c81d2da9777d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-76ae-853e-c81d2da9777d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-76ae-853e-c81d2da9777d" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-76ae-853e-c81d2da9777d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ee9-8703-68bf8914528d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-76ae-853e-c81d2da9777d" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ee9-8703-68bf8914528d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FutureMember_019e6946-fec9-7b1a-bd80-4921fd496947" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FutureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ee9-8703-68bf8914528d" xlink:to="loc_us-gaap_FutureMember_019e6946-fec9-7b1a-bd80-4921fd496947" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ad-99ef-a84e03c745ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-76e3-a4d2-f1b307c44e6a" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ad-99ef-a84e03c745ff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-76ad-99ef-a84e03c745ff_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ad-99ef-a84e03c745ff" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-76ad-99ef-a84e03c745ff_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7f84-b6aa-81fbcf88a133" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ad-99ef-a84e03c745ff" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7f84-b6aa-81fbcf88a133" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7918-af22-95ecfe2dc506" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7f84-b6aa-81fbcf88a133" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7918-af22-95ecfe2dc506" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeAssetFairValueUnsettled_019e6946-fec9-7778-a036-8ec181ee7038" xlink:href="ms-20260630.xsd#ms_DerivativeAssetFairValueUnsettled"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7014-bc07-81b8304ceca1" xlink:to="loc_ms_DerivativeAssetFairValueUnsettled_019e6946-fec9-7778-a036-8ec181ee7038" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesActivityofLevel3AssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesActivityofLevel3AssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesActivityofLevel3AssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueAssetsandLiabilitiesMeasuredonRecurringBasisUnobservableInputReconciliationLineItems_019e6946-fec9-7e21-9a85-7a0ccdb0c605" xlink:href="ms-20260630.xsd#ms_FairValueAssetsandLiabilitiesMeasuredonRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:href="ms-20260630.xsd#ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FairValueAssetsandLiabilitiesMeasuredonRecurringBasisUnobservableInputReconciliationLineItems_019e6946-fec9-7e21-9a85-7a0ccdb0c605" xlink:to="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-767c-b244-d1bc0b1754c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-767c-b244-d1bc0b1754c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-767c-b244-d1bc0b1754c5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-767c-b244-d1bc0b1754c5" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-767c-b244-d1bc0b1754c5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-79d3-868a-e9c4caff4fed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-767c-b244-d1bc0b1754c5" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-79d3-868a-e9c4caff4fed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-716a-b742-9481c61e33c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-79d3-868a-e9c4caff4fed" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-716a-b742-9481c61e33c8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-74c8-ad5b-e1fb31c65aee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-74c8-ad5b-e1fb31c65aee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-74c8-ad5b-e1fb31c65aee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-74c8-ad5b-e1fb31c65aee" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-74c8-ad5b-e1fb31c65aee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-76f1-b9e9-70649f10855e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-74c8-ad5b-e1fb31c65aee" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-76f1-b9e9-70649f10855e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7db7-9577-35896e56ffed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-76f1-b9e9-70649f10855e" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7db7-9577-35896e56ffed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7668-929b-0fe8285e06ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7668-929b-0fe8285e06ee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7668-929b-0fe8285e06ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7668-929b-0fe8285e06ee" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7668-929b-0fe8285e06ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7668-929b-0fe8285e06ee" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-77a0-9653-a2419253ae77" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-77a0-9653-a2419253ae77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-fec9-74ff-b9a1-229401f33a78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-fec9-74ff-b9a1-229401f33a78" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-fec9-717f-94ce-3c830361f68b" xlink:href="ms-20260630.xsd#ms_MortgageAndAssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-fec9-717f-94ce-3c830361f68b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-7d9b-b7a5-e1b2df9cf383" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorDebtObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-7d9b-b7a5-e1b2df9cf383" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-77e7-b216-18ded41ef07e" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-77e7-b216-18ded41ef07e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateEquitiesMember_019e6946-fec9-7fcc-be88-feaecd151c0c" xlink:href="ms-20260630.xsd#ms_CorporateEquitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_ms_CorporateEquitiesMember_019e6946-fec9-7fcc-be88-feaecd151c0c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsMember_019e6946-fec9-7534-a13a-fb8d2feb5c60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_us-gaap_InvestmentsMember_019e6946-fec9-7534-a13a-fb8d2feb5c60" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesAvailableForSaleMember_019e6946-fec9-7b29-89a9-80b575d41459" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesAvailableForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7b19-8b03-9d51f5c4730b" xlink:to="loc_ms_DebtSecuritiesAvailableForSaleMember_019e6946-fec9-7b29-89a9-80b575d41459" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a4a-8515-4ca6d0116f0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a4a-8515-4ca6d0116f0c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7a4a-8515-4ca6d0116f0c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a4a-8515-4ca6d0116f0c" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7a4a-8515-4ca6d0116f0c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a4a-8515-4ca6d0116f0c" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7c02-a76a-5e389dbe4e23" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7c02-a76a-5e389dbe4e23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-7a2a-a27c-f06bb8564ebb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-7a2a-a27c-f06bb8564ebb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-74d0-a9fd-045b72825c92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-74d0-a9fd-045b72825c92" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7c47-ab8a-df3bcaffcdd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7c47-ab8a-df3bcaffcdd1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-733b-976a-2a5b3b65de39" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7f49-9dd1-c99916573975" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-733b-976a-2a5b3b65de39" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-7ac4-8248-7ff561548db6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByLiabilityClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_019e6946-fec9-7054-9af2-8f07ff7b7445" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-7ac4-8248-7ff561548db6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7ac4-8248-7ff561548db6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-7ac4-8248-7ff561548db6" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7ac4-8248-7ff561548db6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019e6946-fec9-7ac4-8248-7ff561548db6" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-707a-a1de-ac7373a92ce0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-707a-a1de-ac7373a92ce0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NonderivativeTradingLiabilitiesMember_019e6946-fec9-7f53-81d4-77f32c8d71ca" xlink:href="ms-20260630.xsd#ms_NonderivativeTradingLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:to="loc_ms_NonderivativeTradingLiabilitiesMember_019e6946-fec9-7f53-81d4-77f32c8d71ca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseMember_019e6946-fec9-7eef-8adf-a4354832aa1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:to="loc_us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseMember_019e6946-fec9-7eef-8adf-a4354832aa1b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherSecuredFinancingsMember_019e6946-fec9-759a-ae03-a83e4b94e514" xlink:href="ms-20260630.xsd#ms_OtherSecuredFinancingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:to="loc_ms_OtherSecuredFinancingsMember_019e6946-fec9-759a-ae03-a83e4b94e514" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BorrowingsMember_019e6946-fec9-71f3-a622-05ca2f56b8fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019e6946-fec9-7648-bd8d-fdadf09daceb" xlink:to="loc_us-gaap_BorrowingsMember_019e6946-fec9-71f3-a622-05ca2f56b8fb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7be0-a2de-764bbadcbad3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7be0-a2de-764bbadcbad3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7ad9-a923-9476890977d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7a0c-b4d8-899b610c17fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-7384-b2a0-d5c7b0dcb751" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7384-b2a0-d5c7b0dcb751_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7233-b929-d40a7637a994" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7dfb-9d15-11416b62a2ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueAssetsandLiabilitiesMeasuredonRecurringBasisUnobservableInputReconciliationLineItems_019e6946-fec9-7e21-9a85-7a0ccdb0c605" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019e6946-fec9-7126-88f8-caa7e5a785b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019e6946-fec9-7126-88f8-caa7e5a785b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019e6946-fec9-78e7-8ea4-4f4189c9264e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019e6946-fec9-78e7-8ea4-4f4189c9264e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019e6946-fec9-743e-b152-0a1c18ef4b33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019e6946-fec9-743e-b152-0a1c18ef4b33" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesAndOriginations_019e6946-fec9-7820-83b7-b0536b7d146f" xlink:href="ms-20260630.xsd#ms_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesAndOriginations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_ms_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesAndOriginations_019e6946-fec9-7820-83b7-b0536b7d146f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_019e6946-fec9-77b6-84df-e0af15f27f98" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_019e6946-fec9-77b6-84df-e0af15f27f98" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues_019e6946-fec9-7109-8e50-30ea2945f55a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues_019e6946-fec9-7109-8e50-30ea2945f55a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_019e6946-fec9-7f53-bff8-117170b7c3e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements_019e6946-fec9-7f53-bff8-117170b7c3e5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_019e6946-fec9-7138-b805-b7c40e61d4a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_019e6946-fec9-7138-b805-b7c40e61d4a3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019e6946-fec9-7d30-aafe-b34720ef989b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_019e6946-fec9-71ea-9431-640981430ce6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-7fdb-b466-86f167519bd5" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_019e6946-fec9-71ea-9431-640981430ce6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueAssetsandLiabilitiesMeasuredonRecurringBasisUnobservableInputReconciliationLineItems_019e6946-fec9-7e21-9a85-7a0ccdb0c605" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019e6946-fec9-776d-99d1-f9ca02f9bfa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019e6946-fec9-776d-99d1-f9ca02f9bfa3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_019e6946-fec9-7ec8-af44-2aad02aa039d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_019e6946-fec9-7ec8-af44-2aad02aa039d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases_019e6946-fec9-73f2-ab3e-e3eb11c3c516" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases_019e6946-fec9-73f2-ab3e-e3eb11c3c516" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales_019e6946-fec9-787b-9f22-1a8779d4b866" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales_019e6946-fec9-787b-9f22-1a8779d4b866" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_019e6946-fec9-7b5f-aaa1-a01e2dc088b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_019e6946-fec9-7b5f-aaa1-a01e2dc088b8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_019e6946-fec9-7e56-8bdb-0ffbc70113be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_019e6946-fec9-7e56-8bdb-0ffbc70113be" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet_019e6946-fec9-7428-ad0d-483904b30bd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet_019e6946-fec9-7428-ad0d-483904b30bd1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019e6946-fec9-7ddd-84b0-0705214bde5a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_019e6946-fec9-7856-aa32-a561dd177ef8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_019e6946-fec9-7856-aa32-a561dd177ef8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome_019e6946-fec9-78a1-a5b9-cfdfd3805825" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6946-fec9-742d-8d3c-40b189e42501" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome_019e6946-fec9-78a1-a5b9-cfdfd3805825" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesValuationTechniquesandSensitivityofUnobservableInputsUsedinLevel3FairValueMeasurementsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesValuationTechniquesandSensitivityofUnobservableInputsUsedinLevel3FairValueMeasurementsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesValuationTechniquesandSensitivityofUnobservableInputsUsedinLevel3FairValueMeasurementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-77b2-adcd-fc5f95166b25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-77b2-adcd-fc5f95166b25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-77b2-adcd-fc5f95166b25_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-77b2-adcd-fc5f95166b25" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-77b2-adcd-fc5f95166b25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7bfa-9517-1a966ec7cd90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-77b2-adcd-fc5f95166b25" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7bfa-9517-1a966ec7cd90" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-747c-8ddf-cccf90e205d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7bfa-9517-1a966ec7cd90" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-747c-8ddf-cccf90e205d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ca-943e-79462b7e4538" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ca-943e-79462b7e4538" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-76ca-943e-79462b7e4538_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ca-943e-79462b7e4538" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-76ca-943e-79462b7e4538_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7a6b-bb0c-5a38c74a7c3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-76ca-943e-79462b7e4538" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7a6b-bb0c-5a38c74a7c3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7848-8177-d3d33bed70d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7a6b-bb0c-5a38c74a7c3a" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-7848-8177-d3d33bed70d7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsNonrecurringMember_019e6946-fec9-76fd-9281-4755f7be418c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7a6b-bb0c-5a38c74a7c3a" xlink:to="loc_us-gaap_FairValueMeasurementsNonrecurringMember_019e6946-fec9-76fd-9281-4755f7be418c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e6946-fec9-7d99-9d53-da9531abf497" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:to="loc_srt_RangeAxis_019e6946-fec9-7d99-9d53-da9531abf497" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6946-fec9-7d99-9d53-da9531abf497_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e6946-fec9-7d99-9d53-da9531abf497" xlink:to="loc_srt_RangeMember_019e6946-fec9-7d99-9d53-da9531abf497_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e6946-fec9-7d99-9d53-da9531abf497" xlink:to="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019e6946-fec9-7577-854f-c98b15d06fbe" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:to="loc_srt_MinimumMember_019e6946-fec9-7577-854f-c98b15d06fbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e6946-fec9-7e16-999f-4a246c21ba14" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:to="loc_srt_MaximumMember_019e6946-fec9-7e16-999f-4a246c21ba14" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_019e6946-fec9-70c1-8ee3-3c544d8a70cd" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:to="loc_srt_WeightedAverageMember_019e6946-fec9-70c1-8ee3-3c544d8a70cd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ArithmeticAverageMember_019e6946-fec9-721a-a42b-d3b39f1ddbb0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ArithmeticAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:to="loc_srt_ArithmeticAverageMember_019e6946-fec9-721a-a42b-d3b39f1ddbb0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MedianMember_019e6946-fec9-7c27-ab77-483f5deabcf4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MedianMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6946-fec9-7b1b-a7f9-82d281b50bca" xlink:to="loc_srt_MedianMember_019e6946-fec9-7c27-ab77-483f5deabcf4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-78f6-8182-a3e9e7a52854" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-78f6-8182-a3e9e7a52854" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-78f6-8182-a3e9e7a52854_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-78f6-8182-a3e9e7a52854" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-78f6-8182-a3e9e7a52854_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-78f6-8182-a3e9e7a52854" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-706e-895b-ca340f797fdf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-fec9-706e-895b-ca340f797fdf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-fec9-7c8f-b161-d311baf9bf3a" xlink:href="ms-20260630.xsd#ms_MortgageAndAssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-fec9-7c8f-b161-d311baf9bf3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-72f7-be29-5e089eaf248c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorDebtObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_us-gaap_SeniorDebtObligationsMember_019e6946-fec9-72f7-be29-5e089eaf248c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-7745-9c4b-1917af939850" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-fec9-7745-9c4b-1917af939850" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7ff1-8733-3ae91051eb77" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7ff1-8733-3ae91051eb77" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-7554-b529-ba3cef6ea1df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-7554-b529-ba3cef6ea1df" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-771f-b4b3-61912248304d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-771f-b4b3-61912248304d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7449-88a4-ef97a0323236" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7449-88a4-ef97a0323236" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-7882-9549-f839c8e9f49f" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7418-9b8b-dfa422b2aa48" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-7882-9549-f839c8e9f49f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_019e6946-fec9-72d1-b8b0-643c71146368" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:to="loc_us-gaap_ValuationTechniqueAxis_019e6946-fec9-72d1-b8b0-643c71146368" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-72d1-b8b0-643c71146368_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019e6946-fec9-72d1-b8b0-643c71146368" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-72d1-b8b0-643c71146368_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019e6946-fec9-72d1-b8b0-643c71146368" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ValuationTechniqueComparablePricingMember_019e6946-fec9-74f8-8dad-4ce3141f5156" xlink:href="ms-20260630.xsd#ms_ValuationTechniqueComparablePricingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_ms_ValuationTechniqueComparablePricingMember_019e6946-fec9-74f8-8dad-4ce3141f5156" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_019e6946-fec9-7f2b-bd4b-ff971670b35d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDiscountedCashFlowMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_019e6946-fec9-7f2b-bd4b-ff971670b35d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueOptionPricingModelMember_019e6946-fec9-7089-97b6-7a77a1cdfa82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueOptionPricingModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_us-gaap_ValuationTechniqueOptionPricingModelMember_019e6946-fec9-7089-97b6-7a77a1cdfa82" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketApproachValuationTechniqueMember_019e6946-fec9-7e1a-a0a3-28d0962d1a5a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketApproachValuationTechniqueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_us-gaap_MarketApproachValuationTechniqueMember_019e6946-fec9-7e1a-a0a3-28d0962d1a5a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDefaultSwapModelMember_019e6946-fec9-722d-bdb8-5c6524613713" xlink:href="ms-20260630.xsd#ms_CreditDefaultSwapModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_ms_CreditDefaultSwapModelMember_019e6946-fec9-722d-bdb8-5c6524613713" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ValuationTechniqueLapseRateMember_019e743b-68f2-7c62-99f1-98875f3309b4" xlink:href="ms-20260630.xsd#ms_ValuationTechniqueLapseRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_ms_ValuationTechniqueLapseRateMember_019e743b-68f2-7c62-99f1-98875f3309b4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ValuationTechniqueCorporateLoanModelMember_019e6946-fec9-738e-ad78-20be4838fe42" xlink:href="ms-20260630.xsd#ms_ValuationTechniqueCorporateLoanModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_ms_ValuationTechniqueCorporateLoanModelMember_019e6946-fec9-738e-ad78-20be4838fe42" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ValuationTechniqueWarehouseModelMember_019e6946-fec9-7689-95a3-edca52603fa6" xlink:href="ms-20260630.xsd#ms_ValuationTechniqueWarehouseModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019e6946-fec9-7680-af70-d4ce23af4ac0" xlink:to="loc_ms_ValuationTechniqueWarehouseModelMember_019e6946-fec9-7689-95a3-edca52603fa6" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_019e6946-fec9-7dbe-a95b-1b27206dd985" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_019e6946-fec9-72ec-99bb-24a4375f986d" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_019e6946-fec9-7dbe-a95b-1b27206dd985" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-7dbe-a95b-1b27206dd985_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019e6946-fec9-7dbe-a95b-1b27206dd985" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-7dbe-a95b-1b27206dd985_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019e6946-fec9-7dbe-a95b-1b27206dd985" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputBondPriceMember_019e6946-fec9-7e02-a5fe-5d84e8a8968e" xlink:href="ms-20260630.xsd#ms_MeasurementInputBondPriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputBondPriceMember_019e6946-fec9-7e02-a5fe-5d84e8a8968e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputLoanPriceMember_019e6946-fec9-7009-88df-c55075f92100" xlink:href="ms-20260630.xsd#ms_MeasurementInputLoanPriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputLoanPriceMember_019e6946-fec9-7009-88df-c55075f92100" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputLossGivenDefaultMember_019e6946-fec9-72dc-a2ea-0eb71d53a79b" xlink:href="ms-20260630.xsd#ms_MeasurementInputLossGivenDefaultMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputLossGivenDefaultMember_019e6946-fec9-72dc-a2ea-0eb71d53a79b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputSharePriceMember_019e6946-fec9-7217-b6dc-5e0dedee531f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputSharePriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_us-gaap_MeasurementInputSharePriceMember_019e6946-fec9-7217-b6dc-5e0dedee531f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputWeightedAverageCostOfCapitalMember_019e6946-fec9-75cb-a3e3-a22ace14c448" xlink:href="ms-20260630.xsd#ms_MeasurementInputWeightedAverageCostOfCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputWeightedAverageCostOfCapitalMember_019e6946-fec9-75cb-a3e3-a22ace14c448" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputExitMultipleMember_019e6946-fec9-79e4-a6c3-7959475c4701" xlink:href="ms-20260630.xsd#ms_MeasurementInputExitMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputExitMultipleMember_019e6946-fec9-79e4-a6c3-7959475c4701" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputEbitdaMultipleMember_019e6946-fec9-765f-9d83-b019ddd3a08b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputEbitdaMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_us-gaap_MeasurementInputEbitdaMultipleMember_019e6946-fec9-765f-9d83-b019ddd3a08b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputInterestRateVolatilitySkewMember_019e6946-fec9-7036-8c1f-3be6a0710562" xlink:href="ms-20260630.xsd#ms_MeasurementInputInterestRateVolatilitySkewMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputInterestRateVolatilitySkewMember_019e6946-fec9-7036-8c1f-3be6a0710562" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputInterestRateCurveCorrelationMember_019e6946-fec9-7027-af3e-2fdb2d3e7ad7" xlink:href="ms-20260630.xsd#ms_MeasurementInputInterestRateCurveCorrelationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputInterestRateCurveCorrelationMember_019e6946-fec9-7027-af3e-2fdb2d3e7ad7" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BondVolatilityMeasurementInputMember_019e6946-fec9-7fcb-a279-b259f30472f7" xlink:href="ms-20260630.xsd#ms_BondVolatilityMeasurementInputMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_BondVolatilityMeasurementInputMember_019e6946-fec9-7fcb-a279-b259f30472f7" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputInflationVolatilityMember_019e6946-fec9-70e4-8642-b3550aa6e148" xlink:href="ms-20260630.xsd#ms_MeasurementInputInflationVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputInflationVolatilityMember_019e6946-fec9-70e4-8642-b3550aa6e148" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputCashSyntheticBasisMember_019e6946-fec9-708b-9c33-76c88aa255dc" xlink:href="ms-20260630.xsd#ms_MeasurementInputCashSyntheticBasisMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputCashSyntheticBasisMember_019e6946-fec9-708b-9c33-76c88aa255dc" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputCreditSpreadMember_019e6946-fec9-7062-9032-233cce6c6f9f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputCreditSpreadMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_us-gaap_MeasurementInputCreditSpreadMember_019e6946-fec9-7062-9032-233cce6c6f9f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputFundingSpreadMember_019e6946-fec9-723e-90f4-1cb940271bd5" xlink:href="ms-20260630.xsd#ms_MeasurementInputFundingSpreadMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputFundingSpreadMember_019e6946-fec9-723e-90f4-1cb940271bd5" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputIswapModelMember_019e743b-68f2-7ace-858b-06e9074d153a" xlink:href="ms-20260630.xsd#ms_MeasurementInputIswapModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputIswapModelMember_019e743b-68f2-7ace-858b-06e9074d153a" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputInterestRateCurveMember_019e6946-fec9-7571-b5e3-bf74017c77c6" xlink:href="ms-20260630.xsd#ms_MeasurementInputInterestRateCurveMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputInterestRateCurveMember_019e6946-fec9-7571-b5e3-bf74017c77c6" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputForeignExchangeVolatilitySkewMember_019e6946-fec9-71c7-836f-c2fcc860ecb3" xlink:href="ms-20260630.xsd#ms_MeasurementInputForeignExchangeVolatilitySkewMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputForeignExchangeVolatilitySkewMember_019e6946-fec9-71c7-836f-c2fcc860ecb3" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputContingencyProbabilityMember_019e6946-fec9-78f6-9f35-d4fd5d6324b5" xlink:href="ms-20260630.xsd#ms_MeasurementInputContingencyProbabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputContingencyProbabilityMember_019e6946-fec9-78f6-9f35-d4fd5d6324b5" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputEquityVolatilityMember_019e6946-fec9-7fe5-bb31-c6cf7c34051a" xlink:href="ms-20260630.xsd#ms_MeasurementInputEquityVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputEquityVolatilityMember_019e6946-fec9-7fe5-bb31-c6cf7c34051a" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputEquityVolatilitySkewMember_019e6946-fec9-7192-9bd1-0d57efc26449" xlink:href="ms-20260630.xsd#ms_MeasurementInputEquityVolatilitySkewMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputEquityVolatilitySkewMember_019e6946-fec9-7192-9bd1-0d57efc26449" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputEquityCorrelationMember_019e6946-fec9-7b25-9513-8560fbafe06b" xlink:href="ms-20260630.xsd#ms_MeasurementInputEquityCorrelationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputEquityCorrelationMember_019e6946-fec9-7b25-9513-8560fbafe06b" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputForeignExchangeCorrelationMember_019e6946-fec9-798d-8c43-446d3ba90714" xlink:href="ms-20260630.xsd#ms_MeasurementInputForeignExchangeCorrelationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputForeignExchangeCorrelationMember_019e6946-fec9-798d-8c43-446d3ba90714" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputInterestRateCorrelationMember_019e6946-fec9-7c85-b2cf-fbd8dbf67c35" xlink:href="ms-20260630.xsd#ms_MeasurementInputInterestRateCorrelationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputInterestRateCorrelationMember_019e6946-fec9-7c85-b2cf-fbd8dbf67c35" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputForwardPowerPriceMember_019e6946-fec9-792d-9264-6a29d57fd283" xlink:href="ms-20260630.xsd#ms_MeasurementInputForwardPowerPriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputForwardPowerPriceMember_019e6946-fec9-792d-9264-6a29d57fd283" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ForwardNaturalGasPriceMember_019e6946-fec9-7067-aee8-59b10bf8c2df" xlink:href="ms-20260630.xsd#ms_ForwardNaturalGasPriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_ForwardNaturalGasPriceMember_019e6946-fec9-7067-aee8-59b10bf8c2df" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputCommodityVolatilityMember_019e6946-fec9-7da0-b6be-488a94e738a4" xlink:href="ms-20260630.xsd#ms_MeasurementInputCommodityVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputCommodityVolatilityMember_019e6946-fec9-7da0-b6be-488a94e738a4" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputCrossCommodityCorrelationMember_019e6946-fec9-7b09-b0a7-45e1e4975968" xlink:href="ms-20260630.xsd#ms_MeasurementInputCrossCommodityCorrelationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputCrossCommodityCorrelationMember_019e6946-fec9-7b09-b0a7-45e1e4975968" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MeasurementInputEquityForeignExchangeCorrelationMember_019e6946-fec9-716c-8535-7a68ad452e19" xlink:href="ms-20260630.xsd#ms_MeasurementInputEquityForeignExchangeCorrelationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e6946-fec9-782a-96fe-ecc6bab27704" xlink:to="loc_ms_MeasurementInputEquityForeignExchangeCorrelationMember_019e6946-fec9-716c-8535-7a68ad452e19" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_019e6946-fec9-7111-9dea-9fae81c84e02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_TradingSecuritiesDebt_019e6946-fec9-7111-9dea-9fae81c84e02" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesTradingMeasurementInput_019e6946-fec9-7c65-87b3-1aca98fe4270" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesTradingMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DebtSecuritiesTradingMeasurementInput_019e6946-fec9-7c65-87b3-1aca98fe4270" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNi_019e6946-fec9-749f-9562-65564a689bfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNi"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_EquitySecuritiesFvNi_019e6946-fec9-749f-9562-65564a689bfe" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiMeasurementInput_019e6946-fec9-774c-890a-bcf334da721b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNiMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_EquitySecuritiesFvNiMeasurementInput_019e6946-fec9-774c-890a-bcf334da721b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AlternativeInvestment_019e6946-fec9-793b-91cd-6998837f0a41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AlternativeInvestment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_AlternativeInvestment_019e6946-fec9-793b-91cd-6998837f0a41" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AlternativeInvestmentMeasurementInput_019e6946-fec9-740e-906c-4f8c3864e5b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AlternativeInvestmentMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_AlternativeInvestmentMeasurementInput_019e6946-fec9-740e-906c-4f8c3864e5b9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019f9080-5b08-7097-8c21-0312f40370ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019f9080-5b08-7097-8c21-0312f40370ae" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleMeasurementInput_019fa3ea-8fbb-7cce-b153-457f54102f63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleMeasurementInput_019fa3ea-8fbb-7cce-b153-457f54102f63" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019e6946-fec9-7381-bac7-e8eca71812a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DerivativeAssets_019e6946-fec9-7381-bac7-e8eca71812a0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetMeasurementInput_019e6946-fec9-7e7a-991e-f29c5c4ee9c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DerivativeAssetMeasurementInput_019e6946-fec9-7e7a-991e-f29c5c4ee9c8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_019e6946-fec9-7f16-9498-d084410a89d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure_019e6946-fec9-7f16-9498-d084410a89d0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesSoldUnderAgreementToRepurchaseMeasurementInput_019e6946-fec9-71b0-9540-12417a390c3e" xlink:href="ms-20260630.xsd#ms_SecuritiesSoldUnderAgreementToRepurchaseMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_ms_SecuritiesSoldUnderAgreementToRepurchaseMeasurementInput_019e6946-fec9-71b0-9540-12417a390c3e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherSecuredFinancings_019e6946-fec9-7564-b1ba-5acfcbbf56e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherSecuredFinancings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_OtherSecuredFinancings_019e6946-fec9-7564-b1ba-5acfcbbf56e3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherSecuredFinancingsMeasurementInput_019e6946-fec9-752b-a606-20a6d4005ef1" xlink:href="ms-20260630.xsd#ms_OtherSecuredFinancingsMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_ms_OtherSecuredFinancingsMeasurementInput_019e6946-fec9-752b-a606-20a6d4005ef1" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_019e6946-fec9-7917-b1c5-7c358a3eede3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DebtInstrumentFairValue_019e6946-fec9-7917-b1c5-7c358a3eede3" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentMeasurementInput_019e6946-fec9-71ea-bfb8-7691ef8114b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_DebtInstrumentMeasurementInput_019e6946-fec9-71ea-bfb8-7691ef8114b4" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansHeldForSaleFairValueDisclosure_019e6946-fec9-7e79-8f76-80abf3b12232" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansHeldForSaleFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_LoansHeldForSaleFairValueDisclosure_019e6946-fec9-7e79-8f76-80abf3b12232" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansHeldForSaleMeasurementInput_019e6946-fec9-7923-9387-c420fb80450f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansHeldForSaleMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_019e6946-fec9-7702-9b99-b3b0dfd8687f" xlink:to="loc_us-gaap_LoansHeldForSaleMeasurementInput_019e6946-fec9-7923-9387-c420fb80450f" xlink:type="arc" order="17"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesFundInterestsMeasuredBasedonNetAssetValueDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesFundInterestsMeasuredBasedonNetAssetValueDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesFundInterestsMeasuredBasedonNetAssetValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7b22-8c0a-413f04451b16" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable_019e6946-fec9-7298-85e0-3df6c5500264" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7b22-8c0a-413f04451b16" xlink:to="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable_019e6946-fec9-7298-85e0-3df6c5500264" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7bd5-b856-3b987d1be865" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable_019e6946-fec9-7298-85e0-3df6c5500264" xlink:to="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7bd5-b856-3b987d1be865" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7bd5-b856-3b987d1be865_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7bd5-b856-3b987d1be865" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7bd5-b856-3b987d1be865_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-765a-a2b6-cc121ba59be9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7bd5-b856-3b987d1be865" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-765a-a2b6-cc121ba59be9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_PrivateEquityAndOtherFundsMember_019e6946-fec9-7868-876d-a36e8b11d4b7" xlink:href="ms-20260630.xsd#ms_PrivateEquityAndOtherFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-765a-a2b6-cc121ba59be9" xlink:to="loc_ms_PrivateEquityAndOtherFundsMember_019e6946-fec9-7868-876d-a36e8b11d4b7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateFundsMember_019e6946-fec9-72e1-aa8f-48051aaf9571" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-765a-a2b6-cc121ba59be9" xlink:to="loc_us-gaap_RealEstateFundsMember_019e6946-fec9-72e1-aa8f-48051aaf9571" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgeFundsMember_019e6946-fec9-7b39-b56b-2563002aa9ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgeFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-765a-a2b6-cc121ba59be9" xlink:to="loc_us-gaap_HedgeFundsMember_019e6946-fec9-7b39-b56b-2563002aa9ea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValueAtCarryingValue_019e6946-fec9-7523-93de-1e5b56f8f510" xlink:href="ms-20260630.xsd#ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValueAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7b22-8c0a-413f04451b16" xlink:to="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValueAtCarryingValue_019e6946-fec9-7523-93de-1e5b56f8f510" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments_019e6946-fec9-768c-9277-adce1d07bd19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7b22-8c0a-413f04451b16" xlink:to="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments_019e6946-fec9-768c-9277-adce1d07bd19" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesNonredeemableFundsbyContractualMaturityDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesNonredeemableFundsbyContractualMaturityDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesNonredeemableFundsbyContractualMaturityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7cea-a81c-b0a75dd6f9d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable_019e6946-fec9-7f21-bc89-1c651df3536a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7cea-a81c-b0a75dd6f9d6" xlink:to="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable_019e6946-fec9-7f21-bc89-1c651df3536a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7102-8d13-2d6d5de404fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable_019e6946-fec9-7f21-bc89-1c651df3536a" xlink:to="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7102-8d13-2d6d5de404fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7102-8d13-2d6d5de404fa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7102-8d13-2d6d5de404fa" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7102-8d13-2d6d5de404fa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7f45-81b8-23d5ed85012f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019e6946-fec9-7102-8d13-2d6d5de404fa" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7f45-81b8-23d5ed85012f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_PrivateEquityAndOtherFundsMember_019e6946-fec9-77b7-a68b-83c92be0431b" xlink:href="ms-20260630.xsd#ms_PrivateEquityAndOtherFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7f45-81b8-23d5ed85012f" xlink:to="loc_ms_PrivateEquityAndOtherFundsMember_019e6946-fec9-77b7-a68b-83c92be0431b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateFundsMember_019e6946-fec9-7a1f-9d50-1751282e9201" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019e6946-fec9-7f45-81b8-23d5ed85012f" xlink:to="loc_us-gaap_RealEstateFundsMember_019e6946-fec9-7a1f-9d50-1751282e9201" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract_019e6946-fec9-70b5-969e-ebe0c4ca9bb9" xlink:href="ms-20260630.xsd#ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLineItems_019e6946-fec9-7cea-a81c-b0a75dd6f9d6" xlink:to="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract_019e6946-fec9-70b5-969e-ebe0c4ca9bb9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NonredeemableFundsMaturityWithinNextFiveYearsAtCarryingValue_019e6946-fec9-7c15-92dc-abd9e42ac74e" xlink:href="ms-20260630.xsd#ms_NonredeemableFundsMaturityWithinNextFiveYearsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract_019e6946-fec9-70b5-969e-ebe0c4ca9bb9" xlink:to="loc_ms_NonredeemableFundsMaturityWithinNextFiveYearsAtCarryingValue_019e6946-fec9-7c15-92dc-abd9e42ac74e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NonredeemableFundsMaturityAfterFiveThroughTenYearsAtCarryingValue_019e6946-fec9-78b7-93c3-709219ee9531" xlink:href="ms-20260630.xsd#ms_NonredeemableFundsMaturityAfterFiveThroughTenYearsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract_019e6946-fec9-70b5-969e-ebe0c4ca9bb9" xlink:to="loc_ms_NonredeemableFundsMaturityAfterFiveThroughTenYearsAtCarryingValue_019e6946-fec9-78b7-93c3-709219ee9531" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NonredeemableFundsMaturityAfterTenYearsAtCarryingValue_019e6946-fec9-7fb3-8097-544bc13da3f3" xlink:href="ms-20260630.xsd#ms_NonredeemableFundsMaturityAfterTenYearsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract_019e6946-fec9-70b5-969e-ebe0c4ca9bb9" xlink:to="loc_ms_NonredeemableFundsMaturityAfterTenYearsAtCarryingValue_019e6946-fec9-7fb3-8097-544bc13da3f3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NonredeemableFundsMaturityAtCarryingValue_019e6946-fec9-7dfb-98b1-8095ccc657e3" xlink:href="ms-20260630.xsd#ms_NonredeemableFundsMaturityAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareRedemptionPeriodAbstract_019e6946-fec9-70b5-969e-ebe0c4ca9bb9" xlink:to="loc_ms_NonredeemableFundsMaturityAtCarryingValue_019e6946-fec9-7dfb-98b1-8095ccc657e3" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesAssetsandLiabilitiesMeasuredatFairValueonaNonrecurringBasisDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesAssetsandLiabilitiesMeasuredatFairValueonaNonrecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesAssetsandLiabilitiesMeasuredatFairValueonaNonrecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7e22-80d4-dec4b54e8b1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-75db-8405-fd90e9ca4558" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7e22-80d4-dec4b54e8b1d" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-75db-8405-fd90e9ca4558" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-726d-bdc4-4b695766d0e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-75db-8405-fd90e9ca4558" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-726d-bdc4-4b695766d0e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-726d-bdc4-4b695766d0e8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-726d-bdc4-4b695766d0e8" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-726d-bdc4-4b695766d0e8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7283-8899-c60b6e13e878" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-726d-bdc4-4b695766d0e8" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7283-8899-c60b6e13e878" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsNonrecurringMember_019e6946-fec9-70fe-87a5-f75651516c58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7283-8899-c60b6e13e878" xlink:to="loc_us-gaap_FairValueMeasurementsNonrecurringMember_019e6946-fec9-70fe-87a5-f75651516c58" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7f9b-ba24-25111bbef62d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-75db-8405-fd90e9ca4558" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7f9b-ba24-25111bbef62d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7f9b-ba24-25111bbef62d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7f9b-ba24-25111bbef62d" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-7f9b-ba24-25111bbef62d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-752b-87ec-853bfd35a103" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-7f9b-ba24-25111bbef62d" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-752b-87ec-853bfd35a103" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e6946-fec9-708a-94c3-d674b66109a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-752b-87ec-853bfd35a103" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e6946-fec9-708a-94c3-d674b66109a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7d00-be24-42e1eb41098b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-752b-87ec-853bfd35a103" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7d00-be24-42e1eb41098b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7229-9e9b-a5ef3dcd9c17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-75db-8405-fd90e9ca4558" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7229-9e9b-a5ef3dcd9c17" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7229-9e9b-a5ef3dcd9c17_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7229-9e9b-a5ef3dcd9c17" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7229-9e9b-a5ef3dcd9c17_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7e00-80e4-7ebebb205403" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7229-9e9b-a5ef3dcd9c17" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7e00-80e4-7ebebb205403" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsMember_019e6946-fec9-7d41-b930-13b42640e49a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7e00-80e4-7ebebb205403" xlink:to="loc_us-gaap_AssetsMember_019e6946-fec9-7d41-b930-13b42640e49a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LendingCommitmentMember_019e6946-fec9-7a99-ad6d-06f5a9d9bf41" xlink:href="ms-20260630.xsd#ms_LendingCommitmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-fec9-7d41-b930-13b42640e49a" xlink:to="loc_ms_LendingCommitmentMember_019e6946-fec9-7a99-ad6d-06f5a9d9bf41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherAssetsOtherInvestmentsMember_019e6961-0e4b-7693-a873-7831486dc170" xlink:href="ms-20260630.xsd#ms_OtherAssetsOtherInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-fec9-7d41-b930-13b42640e49a" xlink:to="loc_ms_OtherAssetsOtherInvestmentsMember_019e6961-0e4b-7693-a873-7831486dc170" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_PropertyPlantAndEquipmentAndCapitalizedSoftwareCostsMember_019e6946-fec9-78f5-9a91-be928bf5b0c7" xlink:href="ms-20260630.xsd#ms_PropertyPlantAndEquipmentAndCapitalizedSoftwareCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-fec9-7d41-b930-13b42640e49a" xlink:to="loc_ms_PropertyPlantAndEquipmentAndCapitalizedSoftwareCostsMember_019e6946-fec9-78f5-9a91-be928bf5b0c7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_RightOfUseAssetsMember_019e7457-13cb-70a1-93da-452e7be5c29c" xlink:href="ms-20260630.xsd#ms_RightOfUseAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-fec9-7d41-b930-13b42640e49a" xlink:to="loc_ms_RightOfUseAssetsMember_019e7457-13cb-70a1-93da-452e7be5c29c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityMember_019e6946-fec9-7589-aa8f-322a2c2511d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7e00-80e4-7ebebb205403" xlink:to="loc_us-gaap_LiabilityMember_019e6946-fec9-7589-aa8f-322a2c2511d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherLiabilitiesAndAccruedExpensesLendingCommitmentsMember_019e6962-d9fb-7d90-8fa6-f315e12707d7" xlink:href="ms-20260630.xsd#ms_OtherLiabilitiesAndAccruedExpensesLendingCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityMember_019e6946-fec9-7589-aa8f-322a2c2511d7" xlink:to="loc_ms_OtherLiabilitiesAndAccruedExpensesLendingCommitmentsMember_019e6962-d9fb-7d90-8fa6-f315e12707d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7bbe-a1c1-98000b655021" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7e22-80d4-dec4b54e8b1d" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7bbe-a1c1-98000b655021" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansHeldForSaleFairValueDisclosure_019e6946-fec9-757e-b704-ba4e3b36b669" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansHeldForSaleFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7bbe-a1c1-98000b655021" xlink:to="loc_us-gaap_LoansHeldForSaleFairValueDisclosure_019e6946-fec9-757e-b704-ba4e3b36b669" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherInvestmentsFairValueDisclosure_019e6946-fec9-70ef-8a04-978b4e9e63cb" xlink:href="ms-20260630.xsd#ms_OtherInvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7bbe-a1c1-98000b655021" xlink:to="loc_ms_OtherInvestmentsFairValueDisclosure_019e6946-fec9-70ef-8a04-978b4e9e63cb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_RightOfUseAssetsFairValueDisclosure_019e6946-fec9-7ecf-b6e1-dc86c85a0752" xlink:href="ms-20260630.xsd#ms_RightOfUseAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7bbe-a1c1-98000b655021" xlink:to="loc_ms_RightOfUseAssetsFairValueDisclosure_019e6946-fec9-7ecf-b6e1-dc86c85a0752" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_019e6946-fec9-7a77-8af6-469ea7735f43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6946-fec9-7bbe-a1c1-98000b655021" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_019e6946-fec9-7a77-8af6-469ea7735f43" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7efb-8bb8-2052ba7ec12e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7e22-80d4-dec4b54e8b1d" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7efb-8bb8-2052ba7ec12e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherLiabilitiesAndAccruedExpensesFairValueDisclosure_019e6946-fec9-781e-b273-12fda86152f7" xlink:href="ms-20260630.xsd#ms_OtherLiabilitiesAndAccruedExpensesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7efb-8bb8-2052ba7ec12e" xlink:to="loc_ms_OtherLiabilitiesAndAccruedExpensesFairValueDisclosure_019e6946-fec9-781e-b273-12fda86152f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_019e6946-fec9-748c-bcf3-fcdce307b0e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6946-fec9-7efb-8bb8-2052ba7ec12e" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_019e6946-fec9-748c-bcf3-fcdce307b0e5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAdjustmentDisclosureAbstract_019e6946-fec9-738b-bdc2-a46bc89a8b18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAdjustmentDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-7e22-80d4-dec4b54e8b1d" xlink:to="loc_us-gaap_FairValueAdjustmentDisclosureAbstract_019e6946-fec9-738b-bdc2-a46bc89a8b18" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1_019e6946-fec9-7862-ae63-128549ea3bb3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionChangesInFairValueGainLoss1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAdjustmentDisclosureAbstract_019e6946-fec9-738b-bdc2-a46bc89a8b18" xlink:to="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1_019e6946-fec9-7862-ae63-128549ea3bb3" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValuesFinancialInstrumentsNotMeasuredatFairValueDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValuesFinancialInstrumentsNotMeasuredatFairValueDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValuesFinancialInstrumentsNotMeasuredatFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019e6946-fec9-76bf-9ac2-381b8227126e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019e6946-fec9-7004-9bda-e6c51b3b67f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByBalanceSheetGroupingTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019e6946-fec9-76bf-9ac2-381b8227126e" xlink:to="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019e6946-fec9-7004-9bda-e6c51b3b67f7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6946-fec9-7af7-9663-8b5df244e107" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019e6946-fec9-7004-9bda-e6c51b3b67f7" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6946-fec9-7af7-9663-8b5df244e107" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6946-fec9-7af7-9663-8b5df244e107_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6946-fec9-7af7-9663-8b5df244e107" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6946-fec9-7af7-9663-8b5df244e107_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e6946-fec9-777b-9180-8675e61ffcb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6946-fec9-7af7-9663-8b5df244e107" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e6946-fec9-777b-9180-8675e61ffcb4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6946-fec9-7fab-96c7-cadc399690a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e6946-fec9-777b-9180-8675e61ffcb4" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6946-fec9-7fab-96c7-cadc399690a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtOtherThanFairValueFairValueDisclosureMember_019e6946-fec9-7499-bef0-53ac957f8504" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtOtherThanFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6946-fec9-7fab-96c7-cadc399690a0" xlink:to="loc_us-gaap_PortionAtOtherThanFairValueFairValueDisclosureMember_019e6946-fec9-7499-bef0-53ac957f8504" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019e6946-fec9-71eb-bb81-dd7340cc48a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6946-fec9-7fab-96c7-cadc399690a0" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019e6946-fec9-71eb-bb81-dd7340cc48a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-75a7-93d0-c11fcab03da6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019e6946-fec9-7004-9bda-e6c51b3b67f7" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-75a7-93d0-c11fcab03da6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-75a7-93d0-c11fcab03da6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-75a7-93d0-c11fcab03da6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-75a7-93d0-c11fcab03da6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-72fd-a241-dca535eb580e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-fec9-75a7-93d0-c11fcab03da6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-72fd-a241-dca535eb580e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019e6946-fec9-71ba-86d1-99a2a52be507" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-72fd-a241-dca535eb580e" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019e6946-fec9-71ba-86d1-99a2a52be507" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e6946-fec9-7af7-bb43-bb0cef66b5cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-72fd-a241-dca535eb580e" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e6946-fec9-7af7-bb43-bb0cef66b5cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7fbd-9c9e-507c67ce3c85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-fec9-72fd-a241-dca535eb580e" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6946-fec9-7fbd-9c9e-507c67ce3c85" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019e6946-fec9-76bf-9ac2-381b8227126e" xlink:to="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019e6946-fec9-77db-8371-fc7b5c9a2682" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019e6946-fec9-77db-8371-fc7b5c9a2682" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-fec9-7139-93fe-a075198174e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-fec9-7139-93fe-a075198174e5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell_019e6946-fec9-7b71-9e94-9d2b3305d9ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell_019e6946-fec9-7b71-9e94-9d2b3305d9ab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesBorrowed_019e6946-fec9-79a8-b5c0-ed57aee9775b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesBorrowed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_SecuritiesBorrowed_019e6946-fec9-79a8-b5c0-ed57aee9775b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_019e6946-fec9-7ccf-aa6d-582a59451d7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_OtherReceivables_019e6946-fec9-7ccf-aa6d-582a59451d7b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-fec9-7b19-bb27-f9e9cd6fde67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-fec9-7b19-bb27-f9e9cd6fde67" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup_019e6946-fec9-7392-abc0-2449f1a0feb8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup_019e6946-fec9-7392-abc0-2449f1a0feb8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashReserveDepositRequiredAndMade_019e6946-fec9-7f6d-a4e7-82b9e24d944a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashReserveDepositRequiredAndMade"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_019e6946-fec9-7007-99c6-2709d877b5b8" xlink:to="loc_us-gaap_CashReserveDepositRequiredAndMade_019e6946-fec9-7f6d-a4e7-82b9e24d944a" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019e6946-fec9-76bf-9ac2-381b8227126e" xlink:to="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Deposits_019e6946-fec9-7cac-a558-6b52790b5d78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Deposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:to="loc_us-gaap_Deposits_019e6946-fec9-7cac-a558-6b52790b5d78" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchase_019e6946-fec9-72a9-a791-e091c959ace6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesSoldUnderAgreementsToRepurchase"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:to="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchase_019e6946-fec9-72a9-a791-e091c959ace6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoaned_019e6946-fec9-769c-984a-7f593d090ca2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesLoaned"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:to="loc_us-gaap_SecuritiesLoaned_019e6946-fec9-769c-984a-7f593d090ca2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherSecuredFinancings_019e6946-fec9-76f2-b82f-b2f285443545" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherSecuredFinancings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:to="loc_us-gaap_OtherSecuredFinancings_019e6946-fec9-76f2-b82f-b2f285443545" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_Payables_019e6946-fec9-71fd-9e25-0105a9d0f0ad" xlink:href="ms-20260630.xsd#ms_Payables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:to="loc_ms_Payables_019e6946-fec9-71fd-9e25-0105a9d0f0ad" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtLongtermAndShorttermCombinedAmount_019e6946-fec9-7368-9d11-c157dad8c0bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtLongtermAndShorttermCombinedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_019e6946-fec9-7867-8a0c-bc3f2ee33334" xlink:to="loc_us-gaap_DebtLongtermAndShorttermCombinedAmount_019e6946-fec9-7368-9d11-c157dad8c0bc" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AdditionalDisclosuresAbstract_019e6946-fec9-7a08-b3a3-7fe033241e0e" xlink:href="ms-20260630.xsd#ms_AdditionalDisclosuresAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019e6946-fec9-76bf-9ac2-381b8227126e" xlink:to="loc_ms_AdditionalDisclosuresAbstract_019e6946-fec9-7a08-b3a3-7fe033241e0e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LoansAndLendingCommitments_019e6946-fec9-7054-ba7a-d6d7d3e20bfb" xlink:href="ms-20260630.xsd#ms_LoansAndLendingCommitments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AdditionalDisclosuresAbstract_019e6946-fec9-7a08-b3a3-7fe033241e0e" xlink:to="loc_ms_LoansAndLendingCommitments_019e6946-fec9-7054-ba7a-d6d7d3e20bfb" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionBorrowingsMeasuredatFairValueonaRecurringBasisDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionBorrowingsMeasuredatFairValueonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionBorrowingsMeasuredatFairValueonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-775c-9324-43598587aced" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7518-8429-3f02a08c7cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-775c-9324-43598587aced" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7518-8429-3f02a08c7cd2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-7410-9bd9-d2a3f24fe9eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7518-8429-3f02a08c7cd2" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-7410-9bd9-d2a3f24fe9eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7410-9bd9-d2a3f24fe9eb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-7410-9bd9-d2a3f24fe9eb" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7410-9bd9-d2a3f24fe9eb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7515-8bbd-b0c53a8584fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6946-fec9-7410-9bd9-d2a3f24fe9eb" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7515-8bbd-b0c53a8584fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-70e5-a5ca-6731b3570041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6946-fec9-7515-8bbd-b0c53a8584fc" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6946-fec9-70e5-a5ca-6731b3570041" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a39-ae6a-8c3e0917f468" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6946-fec9-7518-8429-3f02a08c7cd2" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a39-ae6a-8c3e0917f468" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7a39-ae6a-8c3e0917f468_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a39-ae6a-8c3e0917f468" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7a39-ae6a-8c3e0917f468_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7a39-ae6a-8c3e0917f468" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7b1f-8162-b272ad46752c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7b1f-8162-b272ad46752c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7ea5-84da-03f8bdccbd50" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7ea5-84da-03f8bdccbd50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-79f7-9b76-9bf0b35db921" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-79f7-9b76-9bf0b35db921" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-722a-b9bd-ce926385d7a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-722a-b9bd-ce926385d7a1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7d79-b4d8-07600785a462" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-76f3-a510-becade1859f0" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7d79-b4d8-07600785a462" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_019e6946-fec9-7df7-9b92-fa714ae2b555" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6946-fec9-775c-9324-43598587aced" xlink:to="loc_us-gaap_DebtInstrumentFairValue_019e6946-fec9-7df7-9b92-fa714ae2b555" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionNetRevenuesfromLiabilitiesundertheFairValueOptionDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionNetRevenuesfromLiabilitiesundertheFairValueOptionDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionNetRevenuesfromLiabilitiesundertheFairValueOptionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_019e6946-fec9-7425-80b5-360ad36bd019" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_019e6946-fec9-7425-80b5-360ad36bd019" xlink:to="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-729e-8dbe-e63f1d1da760" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-729e-8dbe-e63f1d1da760" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7441-bf30-33559c2c0f8e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7441-bf30-33559c2c0f8e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtMember_019e6946-fec9-7249-96e9-32c0d5f8537c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:to="loc_us-gaap_DebtMember_019e6946-fec9-7249-96e9-32c0d5f8537c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7c82-aa2e-a15e09a767e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7c82-aa2e-a15e09a767e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1_019e6946-fec9-7170-b6d7-5fd37b6d4b37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionChangesInFairValueGainLoss1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_019e6946-fec9-7425-80b5-360ad36bd019" xlink:to="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1_019e6946-fec9-7170-b6d7-5fd37b6d4b37" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionNetRevenuesfromLiabilitiesundertheFairValueOptionDetails_1" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionNetRevenuesfromLiabilitiesundertheFairValueOptionDetails_1"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionNetRevenuesfromLiabilitiesundertheFairValueOptionDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_019e6946-fec9-7425-80b5-360ad36bd019" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_019e6946-fec9-7425-80b5-360ad36bd019" xlink:to="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-79d1-b414-054a09c8b026" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7441-bf30-33559c2c0f8e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7441-bf30-33559c2c0f8e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7441-bf30-33559c2c0f8e" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtMember_019e6946-fec9-7249-96e9-32c0d5f8537c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:to="loc_us-gaap_DebtMember_019e6946-fec9-7249-96e9-32c0d5f8537c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7c82-aa2e-a15e09a767e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7ef4-823c-e4d0c20d52f7" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7c82-aa2e-a15e09a767e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1_019e6946-fec9-7170-b6d7-5fd37b6d4b37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionChangesInFairValueGainLoss1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresLineItems_019e6946-fec9-7425-80b5-360ad36bd019" xlink:to="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1_019e6946-fec9-7170-b6d7-5fd37b6d4b37" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:href="ms-20260630.xsd#ms_FairValueDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:href="ms-20260630.xsd#ms_LoansAndOtherReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WrittenLoanCommitmentFairValueOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-7881-98c2-5a3ab88de58e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-7881-98c2-5a3ab88de58e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019e6946-fec9-7b6b-a0e1-b8225376c344" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019e6946-fec9-7b6b-a0e1-b8225376c344" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:href="ms-20260630.xsd#ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_1" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_1"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:href="ms-20260630.xsd#ms_FairValueDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:href="ms-20260630.xsd#ms_LoansAndOtherReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WrittenLoanCommitmentFairValueOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:href="ms-20260630.xsd#ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_2" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_2"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_2" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:href="ms-20260630.xsd#ms_FairValueDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:href="ms-20260630.xsd#ms_LoansAndOtherReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WrittenLoanCommitmentFairValueOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019e6946-fec9-7b6b-a0e1-b8225376c344" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019e6946-fec9-7b6b-a0e1-b8225376c344" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:href="ms-20260630.xsd#ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_3" xlink:type="simple" xlink:href="ms-20260630.xsd#FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_3"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/FairValueOptionGainsLossesDuetoChangesinInstrumentSpecificCreditRiskDetails_3" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:href="ms-20260630.xsd#ms_FairValueDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionQuantitativeDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7c59-818a-c8ae8d96e7ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-fec9-7c59-818a-c8ae8d96e7ed" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:href="ms-20260630.xsd#ms_LoansAndOtherReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_ms_LoansAndOtherReceivablesMember_019e6946-fec9-7913-ad17-8e5ed87dafa8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WrittenLoanCommitmentFairValueOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_WrittenLoanCommitmentFairValueOptionMember_019e6946-fec9-76f5-8871-7c28e5320b7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7432-ba9a-8f7f31b30008" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-fec9-7d49-9bc3-7c253e7e48f8" xlink:to="loc_us-gaap_DebtMember_019e6946-fec9-7285-8b83-58a347e7eb1d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-7881-98c2-5a3ab88de58e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueOptionQuantitativeDisclosuresTable_019e6946-fec9-746d-a934-eb7f04956674" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-7881-98c2-5a3ab88de58e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_us-gaap_FairValueOptionCreditRiskGainsLossesOnAssets_019e6946-fec9-7d9c-84b0-ec83022dc2a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:href="ms-20260630.xsd#ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FairValueDisclosureLineItems_019e6946-fec9-7512-b658-4e77fcb8f303" xlink:to="loc_ms_UnrealizedGainLossOnDebtValuationAdjustmentPretaxAccumulatedOtherComprehensiveIncomeLoss_019e6946-fec9-7ae4-9c51-60271cf1b7fd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesFairValuesofDerivativeContractsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesFairValuesofDerivativeContractsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesFairValuesofDerivativeContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_019e6946-fec9-7c85-a25e-9b92983c123c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-736e-97bc-28cce072d846" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019e6946-fec9-7c85-a25e-9b92983c123c" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-736e-97bc-28cce072d846" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodAxis_019eff2b-dc6a-7e90-b228-0634ea96f9b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-736e-97bc-28cce072d846" xlink:to="loc_us-gaap_TransactionMarketMethodAxis_019eff2b-dc6a-7e90-b228-0634ea96f9b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-7e90-b228-0634ea96f9b9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TransactionMarketMethodAxis_019eff2b-dc6a-7e90-b228-0634ea96f9b9" xlink:to="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-7e90-b228-0634ea96f9b9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-782a-856c-ee5d73929773" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TransactionMarketMethodAxis_019eff2b-dc6a-7e90-b228-0634ea96f9b9" xlink:to="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-782a-856c-ee5d73929773" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OverTheCounterMember_019e6946-fec9-7ec4-b330-824960224a35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OverTheCounterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-782a-856c-ee5d73929773" xlink:to="loc_us-gaap_OverTheCounterMember_019e6946-fec9-7ec4-b330-824960224a35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExchangeClearedMember_019e6946-fec9-7151-9778-5186c7fa36fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExchangeClearedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-782a-856c-ee5d73929773" xlink:to="loc_us-gaap_ExchangeClearedMember_019e6946-fec9-7151-9778-5186c7fa36fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExchangeTradedMember_019e6946-fec9-7316-8785-3543d0d47d00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExchangeTradedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff2b-dc6a-782a-856c-ee5d73929773" xlink:to="loc_us-gaap_ExchangeTradedMember_019e6946-fec9-7316-8785-3543d0d47d00" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-7b63-8f60-c8c80e1c0da8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-736e-97bc-28cce072d846" xlink:to="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-7b63-8f60-c8c80e1c0da8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-7b63-8f60-c8c80e1c0da8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-7b63-8f60-c8c80e1c0da8" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-7b63-8f60-c8c80e1c0da8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-7b7d-abda-b19668c14bed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-7b63-8f60-c8c80e1c0da8" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-7b7d-abda-b19668c14bed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6946-fec9-7add-a36d-bb945cd2215e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-7b7d-abda-b19668c14bed" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6946-fec9-7add-a36d-bb945cd2215e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019e6946-fec9-77c2-be8a-3f2906ba16bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-7b7d-abda-b19668c14bed" xlink:to="loc_us-gaap_NondesignatedMember_019e6946-fec9-77c2-be8a-3f2906ba16bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember_019e6946-fec9-7891-8343-92ef07345daf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NondesignatedMember_019e6946-fec9-77c2-be8a-3f2906ba16bd" xlink:to="loc_us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember_019e6946-fec9-7891-8343-92ef07345daf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotDesignatedAsHedgingInstrumentTradingMember_019e6946-fec9-7089-9986-7c946f248f7e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotDesignatedAsHedgingInstrumentTradingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NondesignatedMember_019e6946-fec9-77c2-be8a-3f2906ba16bd" xlink:to="loc_us-gaap_NotDesignatedAsHedgingInstrumentTradingMember_019e6946-fec9-7089-9986-7c946f248f7e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74e4-8f74-994dbbcdeeb7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-736e-97bc-28cce072d846" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74e4-8f74-994dbbcdeeb7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-74e4-8f74-994dbbcdeeb7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74e4-8f74-994dbbcdeeb7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-74e4-8f74-994dbbcdeeb7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74e4-8f74-994dbbcdeeb7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7c08-96a3-136827d48cb7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7c08-96a3-136827d48cb7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7d08-8f6b-84e2643f94ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7d08-8f6b-84e2643f94ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-722c-b8a8-73f5d2963297" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-722c-b8a8-73f5d2963297" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-714a-942e-5e5ddc415aa1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-714a-942e-5e5ddc415aa1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-783b-876f-860c67f533a3" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e60-928b-cb3163d2e25b" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-783b-876f-860c67f533a3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNetAbstract_019e6946-fec9-7048-a989-499776dea3bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019e6946-fec9-7c85-a25e-9b92983c123c" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNetAbstract_019e6946-fec9-7048-a989-499776dea3bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeFairValueOfDerivativeNetAbstract_019e6946-fec9-7048-a989-499776dea3bf" xlink:to="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019e6946-fec9-7d17-95c9-7988aad9d813" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019e6946-fec9-7d17-95c9-7988aad9d813" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019e6946-fec9-7b2e-b16a-a4ee6e2a92a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019e6946-fec9-7b2e-b16a-a4ee6e2a92a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset_019e6946-fec9-7d55-b5bc-28d7c40507e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeAssetCollateralObligationToReturnCashOffset_019e6946-fec9-7d55-b5bc-28d7c40507e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019e6946-fec9-7e94-a87f-f0a7f71e8d7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeAssets_019e6946-fec9-7e94-a87f-f0a7f71e8d7c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeCollateralObligationToReturnSecurities_019e6946-fec9-7f89-96bb-37a8ee34a3f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeCollateralObligationToReturnSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeCollateralObligationToReturnSecurities_019e6946-fec9-7f89-96bb-37a8ee34a3f2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral_019e6946-fec9-7395-b62f-cd808ed3a47d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral_019e6946-fec9-7395-b62f-cd808ed3a47d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement_019e6946-fec9-7dfa-8616-375fe1d8bcfd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeAssetsAbstract_019e6946-fec9-715b-8c98-3adde4390a49" xlink:to="loc_us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangement_019e6946-fec9-7dfa-8616-375fe1d8bcfd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeFairValueOfDerivativeNetAbstract_019e6946-fec9-7048-a989-499776dea3bf" xlink:to="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement_019e6946-fec9-76cd-bc01-b0e95c47b6cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement_019e6946-fec9-76cd-bc01-b0e95c47b6cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityFairValueGrossAsset_019e6946-fec9-7f97-8b0d-80787d56d9f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityFairValueGrossAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeLiabilityFairValueGrossAsset_019e6946-fec9-7f97-8b0d-80787d56d9f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset_019e6946-fec9-7d75-9ce0-9d800aa4c2de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset_019e6946-fec9-7d75-9ce0-9d800aa4c2de" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019e6946-fec9-765d-9994-9e0264f221b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeLiabilities_019e6946-fec9-765d-9994-9e0264f221b2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeCollateralRightToReclaimSecurities_019e6946-fec9-76eb-b492-123230bcaf0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeCollateralRightToReclaimSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeCollateralRightToReclaimSecurities_019e6946-fec9-76eb-b492-123230bcaf0d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral_019e6946-fec9-768d-b01b-81943256fd78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral_019e6946-fec9-768d-b01b-81943256fd78" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement_019e6946-fec9-76fe-a20d-fd90f34141e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLiabilitiesAbstract_019e6946-fec9-7940-87ac-dd7e620d1990" xlink:to="loc_us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangement_019e6946-fec9-76fe-a20d-fd90f34141e0" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesNotionalsofDerivativeContractsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesNotionalsofDerivativeContractsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesNotionalsofDerivativeContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_019e6946-fec9-73d9-a015-ee9352f1a245" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-7089-bca8-03eb9c2430b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019e6946-fec9-73d9-a015-ee9352f1a245" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-7089-bca8-03eb9c2430b5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodAxis_019eff2e-54ab-7861-bc5c-410cf7734f10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-7089-bca8-03eb9c2430b5" xlink:to="loc_us-gaap_TransactionMarketMethodAxis_019eff2e-54ab-7861-bc5c-410cf7734f10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7861-bc5c-410cf7734f10_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TransactionMarketMethodAxis_019eff2e-54ab-7861-bc5c-410cf7734f10" xlink:to="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7861-bc5c-410cf7734f10_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7da3-8dfa-887609dad6ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TransactionMarketMethodAxis_019eff2e-54ab-7861-bc5c-410cf7734f10" xlink:to="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7da3-8dfa-887609dad6ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OverTheCounterMember_019e6946-fec9-7127-ba0b-6b3c7840d3b3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OverTheCounterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7da3-8dfa-887609dad6ec" xlink:to="loc_us-gaap_OverTheCounterMember_019e6946-fec9-7127-ba0b-6b3c7840d3b3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExchangeClearedMember_019e6946-fec9-79a3-8a97-8e4c0e66dabc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExchangeClearedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7da3-8dfa-887609dad6ec" xlink:to="loc_us-gaap_ExchangeClearedMember_019e6946-fec9-79a3-8a97-8e4c0e66dabc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExchangeTradedMember_019e6946-fec9-7915-b53b-43455c94f875" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExchangeTradedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff2e-54ab-7da3-8dfa-887609dad6ec" xlink:to="loc_us-gaap_ExchangeTradedMember_019e6946-fec9-7915-b53b-43455c94f875" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-73f8-b7da-a0e778592951" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-7089-bca8-03eb9c2430b5" xlink:to="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-73f8-b7da-a0e778592951" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-73f8-b7da-a0e778592951_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-73f8-b7da-a0e778592951" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-73f8-b7da-a0e778592951_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-754d-8616-eee9b91063d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6946-fec9-73f8-b7da-a0e778592951" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-754d-8616-eee9b91063d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6946-fec9-7a8b-9632-58001cb8c3df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-754d-8616-eee9b91063d9" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6946-fec9-7a8b-9632-58001cb8c3df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember_019e6946-fec9-70cc-b2fe-40c3c16dba82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-754d-8616-eee9b91063d9" xlink:to="loc_us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember_019e6946-fec9-70cc-b2fe-40c3c16dba82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotDesignatedAsHedgingInstrumentTradingMember_019e6946-fec9-793d-a2bf-b705ed615086" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotDesignatedAsHedgingInstrumentTradingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-754d-8616-eee9b91063d9" xlink:to="loc_us-gaap_NotDesignatedAsHedgingInstrumentTradingMember_019e6946-fec9-793d-a2bf-b705ed615086" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019e6946-fec9-7c2a-8d6b-358faf27f943" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-fec9-754d-8616-eee9b91063d9" xlink:to="loc_us-gaap_NondesignatedMember_019e6946-fec9-7c2a-8d6b-358faf27f943" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74db-8379-ea58b358c5a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019e6946-fec9-7089-bca8-03eb9c2430b5" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74db-8379-ea58b358c5a7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-74db-8379-ea58b358c5a7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74db-8379-ea58b358c5a7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-74db-8379-ea58b358c5a7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-74db-8379-ea58b358c5a7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7186-8138-710c3da43b33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7186-8138-710c3da43b33" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-74a0-9814-b80eb70cf869" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-fec9-74a0-9814-b80eb70cf869" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7ce6-9f70-274617de38dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7ce6-9f70-274617de38dc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7827-937e-4064ac2c3aa8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7827-937e-4064ac2c3aa8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-7717-b8b7-8dfe4c8e7d20" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7dd0-8ab5-b77dd123d34e" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6946-fec9-7717-b8b7-8dfe4c8e7d20" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotionalAmountOfDerivativesAbstract_019e6946-fec9-7ad8-8660-ea07a3946502" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotionalAmountOfDerivativesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019e6946-fec9-73d9-a015-ee9352f1a245" xlink:to="loc_us-gaap_NotionalAmountOfDerivativesAbstract_019e6946-fec9-7ad8-8660-ea07a3946502" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_019e6946-fec9-78e0-b8ff-3e183b3e89a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotionalAmountOfDerivativesAbstract_019e6946-fec9-7ad8-8660-ea07a3946502" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_019e6946-fec9-78e0-b8ff-3e183b3e89a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019e6946-fec9-7515-a74a-d745551dd484" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotionalAmountOfDerivativesAbstract_019e6946-fec9-7ad8-8660-ea07a3946502" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019e6946-fec9-7515-a74a-d745551dd484" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesGainsLossesonAccountingHedgesandFairValueHedgesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesGainsLossesonAccountingHedgesandFairValueHedgesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesGainsLossesonAccountingHedgesandFairValueHedgesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-7a0e-bb0f-d205433aed42_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-7a0e-bb0f-d205433aed42_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_019e6946-fec9-7873-9283-c903a15623e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:to="loc_us-gaap_FairValueHedgingMember_019e6946-fec9-7873-9283-c903a15623e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentHedgingMember_019e6946-fec9-7932-99d7-42d668e939a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetInvestmentHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:to="loc_us-gaap_NetInvestmentHedgingMember_019e6946-fec9-7932-99d7-42d668e939a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-7c40-a35f-65852ac95936" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6946-fec9-7c40-a35f-65852ac95936" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-71b6-a331-36e49942f87f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-71b6-a331-36e49942f87f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7879-80c4-bcc7736ee2f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7879-80c4-bcc7736ee2f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesAvailableForSaleMember_019e6946-fec9-75b9-9147-e5164f504b3f" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesAvailableForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_ms_DebtSecuritiesAvailableForSaleMember_019e6946-fec9-75b9-9147-e5164f504b3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7e04-b7a2-12b22e6df991" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7e04-b7a2-12b22e6df991" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BorrowingsMember_019e6946-fec9-769b-b40e-3505e41bdb33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_BorrowingsMember_019e6946-fec9-769b-b40e-3505e41bdb33" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7557-9ae6-78149a7ea3af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7557-9ae6-78149a7ea3af" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7824-a294-9506860792ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7824-a294-9506860792ca" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SummaryOfFairValueHedgeActivityAbstract_019e6946-fec9-7166-a182-db940bc183c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SummaryOfFairValueHedgeActivityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_SummaryOfFairValueHedgeActivityAbstract_019e6946-fec9-7166-a182-db940bc183c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings_019e6946-fec9-7332-829b-65c666d15e58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SummaryOfFairValueHedgeActivityAbstract_019e6946-fec9-7166-a182-db940bc183c4" xlink:to="loc_us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings_019e6946-fec9-7332-829b-65c666d15e58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeInstrumentsGainLossRecognizedinOtherComprehensiveIncomeLoss_019e6946-fec9-7f25-bd1a-266f04334aae" xlink:href="ms-20260630.xsd#ms_DerivativeInstrumentsGainLossRecognizedinOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:to="loc_ms_DerivativeInstrumentsGainLossRecognizedinOtherComprehensiveIncomeLoss_019e6946-fec9-7f25-bd1a-266f04334aae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet_019e6946-fec9-700d-bcb0-f14d9469abb1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeGainLossOnDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNet_019e6946-fec9-700d-bcb0-f14d9469abb1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateCashFlowHedgesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019e6946-fec9-77b2-b7f4-3bc6ab3a8125" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019e6946-fec9-77b2-b7f4-3bc6ab3a8125" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019e6946-fec9-7c88-b2a1-3cf4a4a5c377" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019e6946-fec9-7c88-b2a1-3cf4a4a5c377" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax_019e6946-fec9-76ff-8b8d-c75b48525ad9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax_019e6946-fec9-76ff-8b8d-c75b48525ad9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_019e6946-fec9-742b-8876-226c897eb11c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_019e6946-fec9-742b-8876-226c897eb11c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTermOfContract_019e6946-fec9-7512-bc4e-f186274e1f31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_DerivativeTermOfContract_019e6946-fec9-7512-bc4e-f186274e1f31" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:href="ms-20260630.xsd#ms_AccountingStandardsUpdate201712Abstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedge_019e6946-fec9-7b34-b23e-b3977a973a31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:to="loc_us-gaap_HedgedAssetFairValueHedge_019e6946-fec9-7b34-b23e-b3977a973a31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-775f-85b2-0251a60ae288" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-775f-85b2-0251a60ae288" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:href="ms-20260630.xsd#ms_BorrowingsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:to="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityFairValueHedge_019e6946-fec9-78ac-b145-ae8fb03ceb73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedLiabilityFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:to="loc_us-gaap_HedgedLiabilityFairValueHedge_019e6946-fec9-78ac-b145-ae8fb03ceb73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7c41-b02a-3644a81b2d01" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:to="loc_us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7c41-b02a-3644a81b2d01" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7ddc-99a5-3b039330a000" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:to="loc_us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7ddc-99a5-3b039330a000" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BeneficialInterestSecuredByPrepayableFinancialInstrumentsLastOfLayerAmortizedCost_019e6946-fec9-76e0-82d1-112b8931d93a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BeneficialInterestSecuredByPrepayableFinancialInstrumentsLastOfLayerAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_BeneficialInterestSecuredByPrepayableFinancialInstrumentsLastOfLayerAmortizedCost_019e6946-fec9-76e0-82d1-112b8931d93a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgePortfolioLayerMethodCumulativeIncreaseDecreaseExcludedFromAmortizedCost_019e6946-fec9-7362-afe7-a5c2720b7ae2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgePortfolioLayerMethodCumulativeIncreaseDecreaseExcludedFromAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgePortfolioLayerMethodCumulativeIncreaseDecreaseExcludedFromAmortizedCost_019e6946-fec9-7362-afe7-a5c2720b7ae2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-fec9-786b-a0bd-d05f8a4ee19b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-fec9-786b-a0bd-d05f8a4ee19b" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesGainsLossesonAccountingHedgesandFairValueHedgesDetails_1" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesGainsLossesonAccountingHedgesandFairValueHedgesDetails_1"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesGainsLossesonAccountingHedgesandFairValueHedgesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-7a0e-bb0f-d205433aed42_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-7a0e-bb0f-d205433aed42_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e6946-fec9-7a0e-bb0f-d205433aed42" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_019e6946-fec9-7873-9283-c903a15623e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:to="loc_us-gaap_FairValueHedgingMember_019e6946-fec9-7873-9283-c903a15623e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentHedgingMember_019e6946-fec9-7932-99d7-42d668e939a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetInvestmentHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e6946-fec9-75a4-9664-5b987abb05ab" xlink:to="loc_us-gaap_NetInvestmentHedgingMember_019e6946-fec9-7932-99d7-42d668e939a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7b98-8822-578e9737636e" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-71b6-a331-36e49942f87f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-71b6-a331-36e49942f87f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-71b6-a331-36e49942f87f" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7879-80c4-bcc7736ee2f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_InterestRateContractMember_019e6946-fec9-7879-80c4-bcc7736ee2f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesAvailableForSaleMember_019e6946-fec9-75b9-9147-e5164f504b3f" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesAvailableForSaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_ms_DebtSecuritiesAvailableForSaleMember_019e6946-fec9-75b9-9147-e5164f504b3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsMember_019e6946-fec9-7e04-b7a2-12b22e6df991" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_DepositsMember_019e6946-fec9-7e04-b7a2-12b22e6df991" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BorrowingsMember_019e6946-fec9-769b-b40e-3505e41bdb33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BorrowingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_BorrowingsMember_019e6946-fec9-769b-b40e-3505e41bdb33" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7557-9ae6-78149a7ea3af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6946-fec9-7557-9ae6-78149a7ea3af" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-fec9-7824-a294-9506860792ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7174-b5f6-889a1c1be295" xlink:to="loc_us-gaap_EquityContractMember_019e6946-fec9-7824-a294-9506860792ca" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SummaryOfFairValueHedgeActivityAbstract_019e6946-fec9-7166-a182-db940bc183c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SummaryOfFairValueHedgeActivityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_SummaryOfFairValueHedgeActivityAbstract_019e6946-fec9-7166-a182-db940bc183c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings_019e6946-fec9-7332-829b-65c666d15e58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SummaryOfFairValueHedgeActivityAbstract_019e6946-fec9-7166-a182-db940bc183c4" xlink:to="loc_us-gaap_GainLossOnFairValueHedgesRecognizedInEarnings_019e6946-fec9-7332-829b-65c666d15e58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeInstrumentsGainLossRecognizedinOtherComprehensiveIncomeLoss_019e6946-fec9-7f25-bd1a-266f04334aae" xlink:href="ms-20260630.xsd#ms_DerivativeInstrumentsGainLossRecognizedinOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:to="loc_ms_DerivativeInstrumentsGainLossRecognizedinOtherComprehensiveIncomeLoss_019e6946-fec9-7f25-bd1a-266f04334aae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet_019e6946-fec9-700d-bcb0-f14d9469abb1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeGainLossOnDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectOfNetInvestmentHedgeOnResultsOfOperationsAbstract_019e6946-fec9-7be1-b14c-8225416ed356" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNet_019e6946-fec9-700d-bcb0-f14d9469abb1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateCashFlowHedgesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019e6946-fec9-77b2-b7f4-3bc6ab3a8125" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019e6946-fec9-77b2-b7f4-3bc6ab3a8125" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019e6946-fec9-7c88-b2a1-3cf4a4a5c377" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019e6946-fec9-7c88-b2a1-3cf4a4a5c377" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax_019e6946-fec9-76ff-8b8d-c75b48525ad9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax_019e6946-fec9-76ff-8b8d-c75b48525ad9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_019e6946-fec9-742b-8876-226c897eb11c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_019e6946-fec9-742b-8876-226c897eb11c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTermOfContract_019e6946-fec9-7512-bc4e-f186274e1f31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCashFlowHedgesAbstract_019e6946-fec9-7ff6-a8a1-f0d4df0cfd34" xlink:to="loc_us-gaap_DerivativeTermOfContract_019e6946-fec9-7512-bc4e-f186274e1f31" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:href="ms-20260630.xsd#ms_AccountingStandardsUpdate201712Abstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedge_019e6946-fec9-7b34-b23e-b3977a973a31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:to="loc_us-gaap_HedgedAssetFairValueHedge_019e6946-fec9-7b34-b23e-b3977a973a31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-775f-85b2-0251a60ae288" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-775f-85b2-0251a60ae288" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:href="ms-20260630.xsd#ms_BorrowingsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AccountingStandardsUpdate201712Abstract_019e6946-fec9-791e-882c-b94772920afc" xlink:to="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityFairValueHedge_019e6946-fec9-78ac-b145-ae8fb03ceb73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedLiabilityFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:to="loc_us-gaap_HedgedLiabilityFairValueHedge_019e6946-fec9-78ac-b145-ae8fb03ceb73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7c41-b02a-3644a81b2d01" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:to="loc_us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7c41-b02a-3644a81b2d01" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7ddc-99a5-3b039330a000" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BorrowingsAbstract_019e6946-fec9-7908-b276-d3afe2700086" xlink:to="loc_us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease_019e6946-fec9-7ddc-99a5-3b039330a000" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BeneficialInterestSecuredByPrepayableFinancialInstrumentsLastOfLayerAmortizedCost_019e6946-fec9-76e0-82d1-112b8931d93a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BeneficialInterestSecuredByPrepayableFinancialInstrumentsLastOfLayerAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_BeneficialInterestSecuredByPrepayableFinancialInstrumentsLastOfLayerAmortizedCost_019e6946-fec9-76e0-82d1-112b8931d93a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgePortfolioLayerMethodCumulativeIncreaseDecreaseExcludedFromAmortizedCost_019e6946-fec9-7362-afe7-a5c2720b7ae2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgePortfolioLayerMethodCumulativeIncreaseDecreaseExcludedFromAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgePortfolioLayerMethodCumulativeIncreaseDecreaseExcludedFromAmortizedCost_019e6946-fec9-7362-afe7-a5c2720b7ae2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-fec9-786b-a0bd-d05f8a4ee19b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-fec9-7703-9e1d-092458a4ee39" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-fec9-786b-a0bd-d05f8a4ee19b" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesEconomicLoanHedgesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesEconomicLoanHedgesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesEconomicLoanHedgesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019e6946-ff8e-7620-a5b9-97ec299e24ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6946-fec9-7975-aead-4816ccac5079" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019e6946-ff8e-7620-a5b9-97ec299e24ca" xlink:to="loc_us-gaap_DerivativeTable_019e6946-fec9-7975-aead-4816ccac5079" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7e71-b0af-6e4b02c4b009" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7975-aead-4816ccac5079" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7e71-b0af-6e4b02c4b009" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e71-b0af-6e4b02c4b009_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7e71-b0af-6e4b02c4b009" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7e71-b0af-6e4b02c4b009_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7b0f-9722-ce976a2a8c67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6946-fec9-7e71-b0af-6e4b02c4b009" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7b0f-9722-ce976a2a8c67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6946-ff8e-755b-a752-b472ce3587e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7b0f-9722-ce976a2a8c67" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6946-ff8e-755b-a752-b472ce3587e8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-ff8e-71ee-89ed-8bff4ef5f476" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6946-fec9-7b0f-9722-ce976a2a8c67" xlink:to="loc_us-gaap_EquityContractMember_019e6946-ff8e-71ee-89ed-8bff4ef5f476" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019e6946-ff8e-7950-b8db-34a799e7c2ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-fec9-7975-aead-4816ccac5079" xlink:to="loc_us-gaap_HedgingDesignationAxis_019e6946-ff8e-7950-b8db-34a799e7c2ad" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6946-ff8e-7950-b8db-34a799e7c2ad_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6946-ff8e-7950-b8db-34a799e7c2ad" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6946-ff8e-7950-b8db-34a799e7c2ad_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6946-ff8e-7a59-a5e3-353700c1df4a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6946-ff8e-7950-b8db-34a799e7c2ad" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6946-ff8e-7a59-a5e3-353700c1df4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember_019e6946-ff8e-739d-b0c9-876cf49443c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6946-ff8e-7a59-a5e3-353700c1df4a" xlink:to="loc_us-gaap_NotDesignatedAsHedgingInstrumentEconomicHedgeMember_019e6946-ff8e-739d-b0c9-876cf49443c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet_019e6946-ff8e-76c7-9645-dcc2f421cdfb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeGainLossOnDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e6946-ff8e-7620-a5b9-97ec299e24ca" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNet_019e6946-ff8e-76c7-9645-dcc2f421cdfb" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesIncrementalCollateralandTerminationPaymentsuponPotentialFutureRatingsDowngradeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesIncrementalCollateralandTerminationPaymentsuponPotentialFutureRatingsDowngradeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesIncrementalCollateralandTerminationPaymentsuponPotentialFutureRatingsDowngradeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-ff8e-70de-98ac-6a22dcdcd7e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6946-ff8e-7c7e-8988-228e06539ec4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-ff8e-70de-98ac-6a22dcdcd7e3" xlink:to="loc_us-gaap_DerivativeTable_019e6946-ff8e-7c7e-8988-228e06539ec4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventAxis_019e6946-ff8e-7ffe-8ddf-3f62879f4d60" xlink:href="ms-20260630.xsd#ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-ff8e-7c7e-8988-228e06539ec4" xlink:to="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventAxis_019e6946-ff8e-7ffe-8ddf-3f62879f4d60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain_019e6946-ff8e-7ffe-8ddf-3f62879f4d60_default" xlink:href="ms-20260630.xsd#ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventAxis_019e6946-ff8e-7ffe-8ddf-3f62879f4d60" xlink:to="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain_019e6946-ff8e-7ffe-8ddf-3f62879f4d60_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain_019e6946-ff8e-76d0-be11-ada434288467" xlink:href="ms-20260630.xsd#ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventAxis_019e6946-ff8e-7ffe-8ddf-3f62879f4d60" xlink:to="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain_019e6946-ff8e-76d0-be11-ada434288467" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringCircumstancesOneNotchCreditRatingDowngradeMember_019e6946-ff8e-7736-92f8-499f714d0ef4" xlink:href="ms-20260630.xsd#ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringCircumstancesOneNotchCreditRatingDowngradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain_019e6946-ff8e-76d0-be11-ada434288467" xlink:to="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringCircumstancesOneNotchCreditRatingDowngradeMember_019e6946-ff8e-7736-92f8-499f714d0ef4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DerivativeCreditRiskRelatedContingentFeaturestriggeringCircumstancesTwoNotchCreditRatingDowngradeMember_019e6946-ff8e-7243-b867-26d12cf28bd1" xlink:href="ms-20260630.xsd#ms_DerivativeCreditRiskRelatedContingentFeaturestriggeringCircumstancesTwoNotchCreditRatingDowngradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_DerivativeCreditRiskRelatedContingentFeaturesTriggeringEventDomain_019e6946-ff8e-76d0-be11-ada434288467" xlink:to="loc_ms_DerivativeCreditRiskRelatedContingentFeaturestriggeringCircumstancesTwoNotchCreditRatingDowngradeMember_019e6946-ff8e-7243-b867-26d12cf28bd1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfArrangementAxis_019e6946-ff8e-76b0-8822-fb4131f65b82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfArrangementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6946-ff8e-7c7e-8988-228e06539ec4" xlink:to="loc_us-gaap_TypeOfArrangementAxis_019e6946-ff8e-76b0-8822-fb4131f65b82" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019e6946-ff8e-76b0-8822-fb4131f65b82_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TypeOfArrangementAxis_019e6946-ff8e-76b0-8822-fb4131f65b82" xlink:to="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019e6946-ff8e-76b0-8822-fb4131f65b82_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019e6946-ff8e-7c7c-969f-d205c0928449" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TypeOfArrangementAxis_019e6946-ff8e-76b0-8822-fb4131f65b82" xlink:to="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019e6946-ff8e-7c7c-969f-d205c0928449" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollaborativeArrangementMember_019e6946-ff8e-7ac5-bdb0-33da1a94bc09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollaborativeArrangementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019e6946-ff8e-7c7c-969f-d205c0928449" xlink:to="loc_us-gaap_CollaborativeArrangementMember_019e6946-ff8e-7ac5-bdb0-33da1a94bc09" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalCollateralAggregateFairValue_019e6946-ff8e-76ba-b52f-576a3dc0cfee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalCollateralAggregateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e6946-ff8e-70de-98ac-6a22dcdcd7e3" xlink:to="loc_us-gaap_AdditionalCollateralAggregateFairValue_019e6946-ff8e-76ba-b52f-576a3dc0cfee" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesMaximumPotentialPayoutNotionalofCreditProtectionSoldDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesMaximumPotentialPayoutNotionalofCreditProtectionSoldDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesMaximumPotentialPayoutNotionalofCreditProtectionSoldDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7d70-a776-c2be38b727af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-783d-877d-6983dbbc604a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfCreditDerivativesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7d70-a776-c2be38b727af" xlink:to="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-783d-877d-6983dbbc604a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-77c2-bb3e-dd65e2109b13" xlink:href="ms-20260630.xsd#ms_CreditDerivativesByMaturityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-783d-877d-6983dbbc604a" xlink:to="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-77c2-bb3e-dd65e2109b13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-77c2-bb3e-dd65e2109b13_default" xlink:href="ms-20260630.xsd#ms_CreditDerivativesByMaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-77c2-bb3e-dd65e2109b13" xlink:to="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-77c2-bb3e-dd65e2109b13_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-70e8-847b-22c72ad13393" xlink:href="ms-20260630.xsd#ms_CreditDerivativesByMaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-77c2-bb3e-dd65e2109b13" xlink:to="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-70e8-847b-22c72ad13393" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LessThanTwelveMonthsFromBalanceSheetDateMember_019e6946-ff8e-7fed-95be-f61ae2240988" xlink:href="ms-20260630.xsd#ms_LessThanTwelveMonthsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-70e8-847b-22c72ad13393" xlink:to="loc_ms_LessThanTwelveMonthsFromBalanceSheetDateMember_019e6946-ff8e-7fed-95be-f61ae2240988" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MoreThanOneAndWithinThreeYearsFromBalanceSheetDateMember_019e6946-ff8e-7a01-b8b9-eaa1742eba0a" xlink:href="ms-20260630.xsd#ms_MoreThanOneAndWithinThreeYearsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-70e8-847b-22c72ad13393" xlink:to="loc_ms_MoreThanOneAndWithinThreeYearsFromBalanceSheetDateMember_019e6946-ff8e-7a01-b8b9-eaa1742eba0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MoreThanThreeAndWithinFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-7c44-9839-0177ee06e7df" xlink:href="ms-20260630.xsd#ms_MoreThanThreeAndWithinFiveYearsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-70e8-847b-22c72ad13393" xlink:to="loc_ms_MoreThanThreeAndWithinFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-7c44-9839-0177ee06e7df" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MoreThanFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-71b5-861e-752efb2b019a" xlink:href="ms-20260630.xsd#ms_MoreThanFiveYearsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-70e8-847b-22c72ad13393" xlink:to="loc_ms_MoreThanFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-71b5-861e-752efb2b019a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-74e8-b6db-e1b6065b7efa" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-783d-877d-6983dbbc604a" xlink:to="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-74e8-b6db-e1b6065b7efa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-74e8-b6db-e1b6065b7efa_default" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-74e8-b6db-e1b6065b7efa" xlink:to="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-74e8-b6db-e1b6065b7efa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-7293-8457-77fc15bd05f7" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-74e8-b6db-e1b6065b7efa" xlink:to="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-7293-8457-77fc15bd05f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesSellingProtectionMember_019e6946-ff8e-7d5d-96dd-db9298bfa063" xlink:href="ms-20260630.xsd#ms_CreditDerivativesSellingProtectionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-7293-8457-77fc15bd05f7" xlink:to="loc_ms_CreditDerivativesSellingProtectionMember_019e6946-ff8e-7d5d-96dd-db9298bfa063" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7f77-bcab-81ac17e24451" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesByContractTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-783d-877d-6983dbbc604a" xlink:to="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7f77-bcab-81ac17e24451" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7f77-bcab-81ac17e24451_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7f77-bcab-81ac17e24451" xlink:to="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7f77-bcab-81ac17e24451_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-78f3-9495-070ebf83da9f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7f77-bcab-81ac17e24451" xlink:to="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-78f3-9495-070ebf83da9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7499-af73-9a68e5996220" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-78f3-9495-070ebf83da9f" xlink:to="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7499-af73-9a68e5996220" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SingleNameCreditDefaultSwapMember_019e6946-ff8e-7969-8254-0573f56a9fa8" xlink:href="ms-20260630.xsd#ms_SingleNameCreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7499-af73-9a68e5996220" xlink:to="loc_ms_SingleNameCreditDefaultSwapMember_019e6946-ff8e-7969-8254-0573f56a9fa8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TotalIndexAndBasketCreditDefaultSwapsMember_019e6946-ff8e-765f-bd20-d94e8653878f" xlink:href="ms-20260630.xsd#ms_TotalIndexAndBasketCreditDefaultSwapsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7499-af73-9a68e5996220" xlink:to="loc_ms_TotalIndexAndBasketCreditDefaultSwapsMember_019e6946-ff8e-765f-bd20-d94e8653878f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCreditDerivativesMember_019e6946-ff8e-7d0e-b51f-36ec2f3a2f38" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCreditDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-78f3-9495-070ebf83da9f" xlink:to="loc_us-gaap_OtherCreditDerivativesMember_019e6946-ff8e-7d0e-b51f-36ec2f3a2f38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7bc4-8e9e-bb29fd1127bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-783d-877d-6983dbbc604a" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7bc4-8e9e-bb29fd1127bc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7bc4-8e9e-bb29fd1127bc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7bc4-8e9e-bb29fd1127bc" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7bc4-8e9e-bb29fd1127bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7d8e-9546-5a91b1ddf52a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7bc4-8e9e-bb29fd1127bc" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7d8e-9546-5a91b1ddf52a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8e-704e-8d14-28c61fe2c3aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7d8e-9546-5a91b1ddf52a" xlink:to="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8e-704e-8d14-28c61fe2c3aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8e-70db-a25a-ebda7c496983" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalNoninvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7d8e-9546-5a91b1ddf52a" xlink:to="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8e-70db-a25a-ebda7c496983" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e6946-ff8e-726e-8301-46039cd5e609" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7d70-a776-c2be38b727af" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e6946-ff8e-726e-8301-46039cd5e609" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativePurchasedCreditProtectionNotionalAmount_019e6946-ff8e-795f-a24f-e7c4542ff101" xlink:href="ms-20260630.xsd#ms_CreditDerivativePurchasedCreditProtectionNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7d70-a776-c2be38b727af" xlink:to="loc_ms_CreditDerivativePurchasedCreditProtectionNotionalAmount_019e6946-ff8e-795f-a24f-e7c4542ff101" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesFairValueAssetLiabilityofCreditProtectionSoldDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesFairValueAssetLiabilityofCreditProtectionSoldDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesFairValueAssetLiabilityofCreditProtectionSoldDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-75ba-b397-e06f744e5fd9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-704e-bf43-98626e3e275f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfCreditDerivativesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-75ba-b397-e06f744e5fd9" xlink:to="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-704e-bf43-98626e3e275f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-70f2-9240-967f18fd8a50" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-704e-bf43-98626e3e275f" xlink:to="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-70f2-9240-967f18fd8a50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-70f2-9240-967f18fd8a50_default" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-70f2-9240-967f18fd8a50" xlink:to="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-70f2-9240-967f18fd8a50_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-7bcb-8b23-e0fbc7b92756" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-70f2-9240-967f18fd8a50" xlink:to="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-7bcb-8b23-e0fbc7b92756" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesSellingProtectionMember_019e6946-ff8e-7afe-905c-536045e2ad55" xlink:href="ms-20260630.xsd#ms_CreditDerivativesSellingProtectionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-7bcb-8b23-e0fbc7b92756" xlink:to="loc_ms_CreditDerivativesSellingProtectionMember_019e6946-ff8e-7afe-905c-536045e2ad55" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7eca-805e-5e7201fbd8f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesByContractTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-704e-bf43-98626e3e275f" xlink:to="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7eca-805e-5e7201fbd8f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7eca-805e-5e7201fbd8f8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7eca-805e-5e7201fbd8f8" xlink:to="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7eca-805e-5e7201fbd8f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7a5d-8a98-f413861d7e68" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-7eca-805e-5e7201fbd8f8" xlink:to="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7a5d-8a98-f413861d7e68" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-70a0-b572-cee171a3a516" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7a5d-8a98-f413861d7e68" xlink:to="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-70a0-b572-cee171a3a516" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SingleNameCreditDefaultSwapMember_019e6946-ff8e-7886-8536-ffefce9669dc" xlink:href="ms-20260630.xsd#ms_SingleNameCreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-70a0-b572-cee171a3a516" xlink:to="loc_ms_SingleNameCreditDefaultSwapMember_019e6946-ff8e-7886-8536-ffefce9669dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TotalIndexAndBasketCreditDefaultSwapsMember_019e6946-ff8e-7615-bbad-0e99e98f4095" xlink:href="ms-20260630.xsd#ms_TotalIndexAndBasketCreditDefaultSwapsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-70a0-b572-cee171a3a516" xlink:to="loc_ms_TotalIndexAndBasketCreditDefaultSwapsMember_019e6946-ff8e-7615-bbad-0e99e98f4095" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCreditDerivativesMember_019e6946-ff8e-7e1b-b126-0b8eb9151535" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCreditDerivativesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7a5d-8a98-f413861d7e68" xlink:to="loc_us-gaap_OtherCreditDerivativesMember_019e6946-ff8e-7e1b-b126-0b8eb9151535" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7594-bbd8-0739cfa58cf3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-704e-bf43-98626e3e275f" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7594-bbd8-0739cfa58cf3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7594-bbd8-0739cfa58cf3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7594-bbd8-0739cfa58cf3" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7594-bbd8-0739cfa58cf3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7111-ac5e-de47c1ccc254" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7594-bbd8-0739cfa58cf3" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7111-ac5e-de47c1ccc254" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8e-7e7b-aad4-ba93b14f14ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7111-ac5e-de47c1ccc254" xlink:to="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8e-7e7b-aad4-ba93b14f14ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8e-720e-a3c7-12d051a44b11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalNoninvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7111-ac5e-de47c1ccc254" xlink:to="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8e-720e-a3c7-12d051a44b11" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskDerivativesAtFairValueNet_019e6946-ff8e-7a00-befd-da17bbbc0224" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskDerivativesAtFairValueNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-75ba-b397-e06f744e5fd9" xlink:to="loc_us-gaap_CreditRiskDerivativesAtFairValueNet_019e6946-ff8e-7a00-befd-da17bbbc0224" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesProtectionPurchasedwithCDSDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#DerivativeInstrumentsandHedgingActivitiesProtectionPurchasedwithCDSDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/DerivativeInstrumentsandHedgingActivitiesProtectionPurchasedwithCDSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7318-b2e0-1fbe889f4df2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-7287-a24d-fc3d06bc1d99" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfCreditDerivativesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7318-b2e0-1fbe889f4df2" xlink:to="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-7287-a24d-fc3d06bc1d99" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-76e5-a004-821dd5dfa176" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-7287-a24d-fc3d06bc1d99" xlink:to="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-76e5-a004-821dd5dfa176" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-76e5-a004-821dd5dfa176_default" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-76e5-a004-821dd5dfa176" xlink:to="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-76e5-a004-821dd5dfa176_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-70e8-922f-d62ae1f21e2d" xlink:href="ms-20260630.xsd#ms_CreditDerivativesProtectionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_CreditDerivativesProtectionAxis_019e6946-ff8e-76e5-a004-821dd5dfa176" xlink:to="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-70e8-922f-d62ae1f21e2d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDefaultSwapBuyingProtectionMember_019e6946-ff8e-7869-aea2-81def635a6f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDefaultSwapBuyingProtectionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesProtectionDomain_019e6946-ff8e-70e8-922f-d62ae1f21e2d" xlink:to="loc_us-gaap_CreditDefaultSwapBuyingProtectionMember_019e6946-ff8e-7869-aea2-81def635a6f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-75d0-af2d-9cdce30b2d68" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesByContractTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfCreditDerivativesTable_019e6946-ff8e-7287-a24d-fc3d06bc1d99" xlink:to="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-75d0-af2d-9cdce30b2d68" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-75d0-af2d-9cdce30b2d68_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-75d0-af2d-9cdce30b2d68" xlink:to="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-75d0-af2d-9cdce30b2d68_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7c72-a2d2-16cb22f41479" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDerivativesContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditDerivativesByContractTypeAxis_019e6946-ff8e-75d0-af2d-9cdce30b2d68" xlink:to="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7c72-a2d2-16cb22f41479" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7881-a801-d337465e8087" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesContractTypeDomain_019e6946-ff8e-7c72-a2d2-16cb22f41479" xlink:to="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7881-a801-d337465e8087" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SingleNameCreditDefaultSwapMember_019e6946-ff8e-7595-8928-2d0f60a559aa" xlink:href="ms-20260630.xsd#ms_SingleNameCreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7881-a801-d337465e8087" xlink:to="loc_ms_SingleNameCreditDefaultSwapMember_019e6946-ff8e-7595-8928-2d0f60a559aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_IndexAndBasketCreditDefaultSwapMember_019e6946-ff8e-75a7-bfad-4bb166e75ad6" xlink:href="ms-20260630.xsd#ms_IndexAndBasketCreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7881-a801-d337465e8087" xlink:to="loc_ms_IndexAndBasketCreditDefaultSwapMember_019e6946-ff8e-75a7-bfad-4bb166e75ad6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TranchedIndexAndBasketCreditDefaultSwapMember_019e6946-ff8e-7095-ac62-a9bcbf9b1836" xlink:href="ms-20260630.xsd#ms_TranchedIndexAndBasketCreditDefaultSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDefaultSwapMember_019e6946-ff8e-7881-a801-d337465e8087" xlink:to="loc_ms_TranchedIndexAndBasketCreditDefaultSwapMember_019e6946-ff8e-7095-ac62-a9bcbf9b1836" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e6946-ff8e-71e9-a1c6-f216d5bce1fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7318-b2e0-1fbe889f4df2" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e6946-ff8e-71e9-a1c6-f216d5bce1fe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskDerivativesAtFairValueNet_019e6946-ff8e-7908-8fc1-95154d7fca77" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskDerivativesAtFairValueNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditDerivativesLineItems_019e6946-ff8e-7318-b2e0-1fbe889f4df2" xlink:to="loc_us-gaap_CreditRiskDerivativesAtFairValueNet_019e6946-ff8e-7908-8fc1-95154d7fca77" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/InvestmentSecuritiesAFSandHTMSecuritiesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#InvestmentSecuritiesAFSandHTMSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/InvestmentSecuritiesAFSandHTMSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:href="ms-20260630.xsd#ms_ScheduleOfMarketableSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-70a9-89de-fe54acf17759" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-70a9-89de-fe54acf17759" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7348-bb7a-b0865f753b58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-70a9-89de-fe54acf17759" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7348-bb7a-b0865f753b58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7348-bb7a-b0865f753b58_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7348-bb7a-b0865f753b58" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7348-bb7a-b0865f753b58_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-75e9-b989-86a2e65927ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7348-bb7a-b0865f753b58" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-75e9-b989-86a2e65927ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-73e9-ba39-83c6371c54a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-75e9-b989-86a2e65927ff" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-73e9-ba39-83c6371c54a1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_019e6946-ff8e-75e4-830b-0ea220209127" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-73e9-ba39-83c6371c54a1" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_019e6946-ff8e-75e4-830b-0ea220209127" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_019e6946-ff8e-7215-a150-0b230aa553dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-73e9-ba39-83c6371c54a1" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_019e6946-ff8e-7215-a150-0b230aa553dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-713b-9c41-de046ce99cd0" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-75e9-b989-86a2e65927ff" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-713b-9c41-de046ce99cd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8e-7d92-a8e2-4680c39c6a3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-713b-9c41-de046ce99cd0" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8e-7d92-a8e2-4680c39c6a3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-ff8e-7df6-a85c-e91d71b38a5a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-713b-9c41-de046ce99cd0" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-ff8e-7df6-a85c-e91d71b38a5a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember_019e6946-ff8e-7ebf-8e30-0cc5da6ff849" xlink:href="ms-20260630.xsd#ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-713b-9c41-de046ce99cd0" xlink:to="loc_ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember_019e6946-ff8e-7ebf-8e30-0cc5da6ff849" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e6946-ff8e-737c-93c0-66ae1d02ea26" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-713b-9c41-de046ce99cd0" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e6946-ff8e-737c-93c0-66ae1d02ea26" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-ff8e-7a7f-b577-a9d37722f197" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-ff8e-7a7f-b577-a9d37722f197" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019e6946-ff8e-78b6-b8b7-029379efdd62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019e6946-ff8e-78b6-b8b7-029379efdd62" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019e6946-ff8e-7c3f-ae07-cd8c18fb74f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019e6946-ff8e-7c3f-ae07-cd8c18fb74f6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e6946-ff8e-7b02-8d3d-f48753d5eb02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e6946-ff8e-7b02-8d3d-f48753d5eb02" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-ff8e-7812-9045-436ccad284d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-ff8e-7812-9045-436ccad284d1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedGainBeforeTaxCumulativeIncreaseDecrease_019e6946-ff8e-7041-914e-a0ae5a73dd53" xlink:href="ms-20260630.xsd#ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedGainBeforeTaxCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedGainBeforeTaxCumulativeIncreaseDecrease_019e6946-ff8e-7041-914e-a0ae5a73dd53" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedLossBeforeTaxCumulativeIncreaseDecrease_019e6946-ff8e-79db-8927-34ba6be35e93" xlink:href="ms-20260630.xsd#ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedLossBeforeTaxCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract_019e6946-ff8e-7599-8f7b-726dcf33b35c" xlink:to="loc_ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedLossBeforeTaxCumulativeIncreaseDecrease_019e6946-ff8e-79db-8927-34ba6be35e93" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e6946-ff8e-7773-a127-88910b17f3c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e6946-ff8e-7773-a127-88910b17f3c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_019e6946-ff8e-7b83-a649-402222134e40" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e6946-ff8e-7773-a127-88910b17f3c1" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_019e6946-ff8e-7b83-a649-402222134e40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain_019e6946-ff8e-788d-9d08-e3f705d2b487" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e6946-ff8e-7773-a127-88910b17f3c1" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain_019e6946-ff8e-788d-9d08-e3f705d2b487" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss_019e6946-ff8e-7e11-9457-884bedc63073" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e6946-ff8e-7773-a127-88910b17f3c1" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss_019e6946-ff8e-7e11-9457-884bedc63073" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e6946-ff8e-797a-b5f4-3646cff5c069" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e6946-ff8e-7773-a127-88910b17f3c1" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e6946-ff8e-797a-b5f4-3646cff5c069" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentSecuritiesAmortizedCost_019e6946-ff8e-7fcf-8bcc-43a77171f6da" xlink:href="ms-20260630.xsd#ms_InvestmentSecuritiesAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_ms_InvestmentSecuritiesAmortizedCost_019e6946-ff8e-7fcf-8bcc-43a77171f6da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019e6946-ff8e-7e91-90bc-08d23fe75a3a" xlink:href="ms-20260630.xsd#ms_InvestmentSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_ms_InvestmentSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019e6946-ff8e-7e91-90bc-08d23fe75a3a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019e6946-ff8e-7049-b08a-4a58209fbb23" xlink:href="ms-20260630.xsd#ms_InvestmentSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_ms_InvestmentSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019e6946-ff8e-7049-b08a-4a58209fbb23" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-ff8e-72e9-a541-a91f092d8543" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-ff8e-72e9-a541-a91f092d8543" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesThirdPartyGuaranteesPercent_019e6946-ff8e-7d0d-bb60-7becca2feb91" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesThirdPartyGuaranteesPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-709f-a1a7-ebdf8088378b" xlink:to="loc_ms_AvailableForSaleSecuritiesThirdPartyGuaranteesPercent_019e6946-ff8e-7d0d-bb60-7becca2feb91" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/InvestmentSecuritiesAFSSecuritiesinanUnrealizedLossPositionDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#InvestmentSecuritiesAFSSecuritiesinanUnrealizedLossPositionDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/InvestmentSecuritiesAFSSecuritiesinanUnrealizedLossPositionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e6946-ff8e-7ff7-87d9-249212892eeb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-720d-880e-965de9636cbd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e6946-ff8e-7ff7-87d9-249212892eeb" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-720d-880e-965de9636cbd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-79dd-8584-df36db3b35fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-720d-880e-965de9636cbd" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-79dd-8584-df36db3b35fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-79dd-8584-df36db3b35fe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-79dd-8584-df36db3b35fe" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-79dd-8584-df36db3b35fe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7251-9c20-164d988e8814" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-79dd-8584-df36db3b35fe" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7251-9c20-164d988e8814" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7d75-84af-36841ec257cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7251-9c20-164d988e8814" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7d75-84af-36841ec257cb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_019e6946-ff8e-7907-a67f-851e0f248d8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7d75-84af-36841ec257cb" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_019e6946-ff8e-7907-a67f-851e0f248d8a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_019e6946-ff8e-7193-a600-03bbb8572c0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7d75-84af-36841ec257cb" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_019e6946-ff8e-7193-a600-03bbb8572c0a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-721a-928c-29b56761ce61" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7251-9c20-164d988e8814" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-721a-928c-29b56761ce61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8e-70d8-b840-dba5f0c68a65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-721a-928c-29b56761ce61" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8e-70d8-b840-dba5f0c68a65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-ff8e-7aae-a15f-928c9aef4181" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-721a-928c-29b56761ce61" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-ff8e-7aae-a15f-928c9aef4181" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember_019e6946-ff8e-7f0c-be12-f0da0e49952c" xlink:href="ms-20260630.xsd#ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-721a-928c-29b56761ce61" xlink:to="loc_ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember_019e6946-ff8e-7f0c-be12-f0da0e49952c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e6946-ff8e-7ff7-87d9-249212892eeb" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_019e6946-ff8e-7424-9c5a-f3c5ab89f8aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_019e6946-ff8e-7424-9c5a-f3c5ab89f8aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_019e6946-ff8e-771b-9b5b-57ac2c36f855" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_019e6946-ff8e-771b-9b5b-57ac2c36f855" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_019e6946-ff8e-76b2-8432-bb60138768d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_019e6946-ff8e-76b2-8432-bb60138768d0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_019e6946-ff8e-715b-a0d9-c7552ab100d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_019e6946-ff8e-715b-a0d9-c7552ab100d1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_019e6946-ff8e-71f4-9e4e-ef941a241d8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_019e6946-ff8e-71f4-9e4e-ef941a241d8e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedLossBeforeTaxCumulativeIncreaseDecrease_019e6946-ff8e-7657-91d5-c9aea9a9c9a8" xlink:href="ms-20260630.xsd#ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedLossBeforeTaxCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_ms_HedgedAssetFairValueHedgePortfolioLayerMethodHedgedLayerAccumulatedGrossUnrealizedLossBeforeTaxCumulativeIncreaseDecrease_019e6946-ff8e-7657-91d5-c9aea9a9c9a8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_019e6946-ff8e-75ba-8348-6e50f949f7a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionQualitativeDisclosureAbstract_019e6946-ff8e-7dde-be5e-c9b28ae20fd8" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_019e6946-ff8e-75ba-8348-6e50f949f7a4" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/InvestmentSecuritiesNarrativeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#InvestmentSecuritiesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/InvestmentSecuritiesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e6946-ff8e-76c6-ad63-0841f8ae73e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesTable_019e6946-ff8e-764c-8e97-e2f283afae01" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfHeldToMaturitySecuritiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e6946-ff8e-76c6-ad63-0841f8ae73e3" xlink:to="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesTable_019e6946-ff8e-764c-8e97-e2f283afae01" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7234-9403-4036255f1aef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesTable_019e6946-ff8e-764c-8e97-e2f283afae01" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7234-9403-4036255f1aef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7234-9403-4036255f1aef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7234-9403-4036255f1aef" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7234-9403-4036255f1aef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-72d7-a4dd-4fd06690a4e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7234-9403-4036255f1aef" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-72d7-a4dd-4fd06690a4e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e6946-ff8e-704e-96e1-d8d818cb01f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-72d7-a4dd-4fd06690a4e0" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e6946-ff8e-704e-96e1-d8d818cb01f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-77f9-970b-34dab05f6a67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e6946-ff8e-76c6-ad63-0841f8ae73e3" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-77f9-970b-34dab05f6a67" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesHeldToMaturityInvestmentGradePercent_019e6946-ff8e-745c-b88c-abe93435a521" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesHeldToMaturityInvestmentGradePercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e6946-ff8e-76c6-ad63-0841f8ae73e3" xlink:to="loc_ms_DebtSecuritiesHeldToMaturityInvestmentGradePercent_019e6946-ff8e-745c-b88c-abe93435a521" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/InvestmentSecuritiesInvestmentSecuritiesbyContractualMaturityDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#InvestmentSecuritiesInvestmentSecuritiesbyContractualMaturityDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/InvestmentSecuritiesInvestmentSecuritiesbyContractualMaturityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-774b-98bd-5e75c0aff3c7" xlink:href="ms-20260630.xsd#ms_ScheduleOfMarketableSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-785b-8c54-4af9273f1adb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-774b-98bd-5e75c0aff3c7" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-785b-8c54-4af9273f1adb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7f18-8c47-f2c3dbd75599" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e6946-ff8e-785b-8c54-4af9273f1adb" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7f18-8c47-f2c3dbd75599" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7f18-8c47-f2c3dbd75599_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7f18-8c47-f2c3dbd75599" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7f18-8c47-f2c3dbd75599_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-737f-b664-b62488367fee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-7f18-8c47-f2c3dbd75599" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-737f-b664-b62488367fee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7173-880a-26f326761b7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-737f-b664-b62488367fee" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7173-880a-26f326761b7d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_019e6946-ff8e-7bce-b9ec-81e1af1f8829" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7173-880a-26f326761b7d" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_019e6946-ff8e-7bce-b9ec-81e1af1f8829" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_019e6946-ff8e-771c-b5a1-da8bdb260147" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7173-880a-26f326761b7d" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_019e6946-ff8e-771c-b5a1-da8bdb260147" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-7a06-8741-635aad1f8a19" xlink:href="ms-20260630.xsd#ms_CorporateandOtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-737f-b664-b62488367fee" xlink:to="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-7a06-8741-635aad1f8a19" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8e-76f4-92f8-d19ba859cb9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-7a06-8741-635aad1f8a19" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8e-76f4-92f8-d19ba859cb9d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-ff8e-7b88-9eb0-4b1ef647d761" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-7a06-8741-635aad1f8a19" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e6946-ff8e-7b88-9eb0-4b1ef647d761" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember_019e6946-ff8e-70e8-8590-4452110fb3cc" xlink:href="ms-20260630.xsd#ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-7a06-8741-635aad1f8a19" xlink:to="loc_ms_AssetBackedSecuritiesFederalFamilyEducationLoanProgramMember_019e6946-ff8e-70e8-8590-4452110fb3cc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e6946-ff8e-7595-bd97-cd7a00d97569" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CorporateandOtherDebtSecuritiesMember_019e6946-ff8e-7a06-8741-635aad1f8a19" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e6946-ff8e-7595-bd97-cd7a00d97569" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-774b-98bd-5e75c0aff3c7" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019e6946-ff8e-70d3-b794-71e5324cb202" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019e6946-ff8e-70d3-b794-71e5324cb202" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019e6946-ff8e-76bf-942a-951a32cca3d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019e6946-ff8e-76bf-942a-951a32cca3d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_019e6946-ff8e-7a05-95a3-91ee5cdd46f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_019e6946-ff8e-7a05-95a3-91ee5cdd46f4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost_019e6946-ff8e-78ba-bc7b-9a8091e80cb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost_019e6946-ff8e-78ba-bc7b-9a8091e80cb5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-ff8e-7d6a-90b9-973a4c356b9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-ff8e-7d6a-90b9-973a4c356b9d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-ff8e-76a5-832f-ec4c6ed05416" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerCumulativeIncreaseDecrease_019e6946-ff8e-76a5-832f-ec4c6ed05416" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesHeldtomaturityMaturityAllocatedandSingleMaturityDateRollingwithinOneYearAmortizedCostLessAllowanceforCreditLoss_019e6946-ff8e-7e1f-aea6-669717e88e39" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesHeldtomaturityMaturityAllocatedandSingleMaturityDateRollingwithinOneYearAmortizedCostLessAllowanceforCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_ms_DebtSecuritiesHeldtomaturityMaturityAllocatedandSingleMaturityDateRollingwithinOneYearAmortizedCostLessAllowanceforCreditLoss_019e6946-ff8e-7e1f-aea6-669717e88e39" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfterOneThroughFiveYearsAmortizedCostLessAllowanceForCreditLoss_019e6946-ff8e-7e91-94e2-aab89328074c" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfterOneThroughFiveYearsAmortizedCostLessAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfterOneThroughFiveYearsAmortizedCostLessAllowanceForCreditLoss_019e6946-ff8e-7e91-94e2-aab89328074c" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfterFiveThroughTenYearsAmortizedCostLessAllowanceForCreditLoss_019e6946-ff8e-79da-a93a-352b3d5e9ac8" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfterFiveThroughTenYearsAmortizedCostLessAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfterFiveThroughTenYearsAmortizedCostLessAllowanceForCreditLoss_019e6946-ff8e-79da-a93a-352b3d5e9ac8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfter10YearsAmortizedCostLessAllowanceForCreditLoss_019e6946-ff8e-759e-a190-8c74681bf456" xlink:href="ms-20260630.xsd#ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfter10YearsAmortizedCostLessAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_ms_DebtSecuritiesHeldToMaturityMaturityAllocatedAndSingleMaturityDateRollingAfter10YearsAmortizedCostLessAllowanceForCreditLoss_019e6946-ff8e-759e-a190-8c74681bf456" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_019e6946-ff8e-7c8a-8531-b585554f1d9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_019e6946-ff8e-7c8a-8531-b585554f1d9d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentSecuritiesAmortizedCost_019e6946-ff8e-7426-946d-dd6a7627ae98" xlink:href="ms-20260630.xsd#ms_InvestmentSecuritiesAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e6946-ff8e-774d-90df-8f783caf3051" xlink:to="loc_ms_InvestmentSecuritiesAmortizedCost_019e6946-ff8e-7426-946d-dd6a7627ae98" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-774b-98bd-5e75c0aff3c7" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019e6946-ff8e-78a1-8b0c-bd8393a71c2f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019e6946-ff8e-78a1-8b0c-bd8393a71c2f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e6946-ff8e-7669-8491-d761092bc526" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e6946-ff8e-7669-8491-d761092bc526" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e6946-ff8e-7807-b613-5e8e359d595b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e6946-ff8e-7807-b613-5e8e359d595b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_019e6946-ff8e-745a-9916-c0cd0fdbd4bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_019e6946-ff8e-745a-9916-c0cd0fdbd4bd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e6946-ff8e-77b8-852e-c05ea74cc5af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e6946-ff8e-77b8-852e-c05ea74cc5af" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue_019e6946-ff8e-7172-abd6-f8494f762e2e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue_019e6946-ff8e-7172-abd6-f8494f762e2e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e6946-ff8e-77c1-8692-f0c54790298b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e6946-ff8e-77c1-8692-f0c54790298b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e6946-ff8e-70d6-9099-9b28f16c0548" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e6946-ff8e-70d6-9099-9b28f16c0548" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue_019e6946-ff8e-768c-983a-baaeb3c30dbd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue_019e6946-ff8e-768c-983a-baaeb3c30dbd" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e6946-ff8e-7fc5-8b70-ab88183a17f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e6946-ff8e-7fc5-8b70-ab88183a17f0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-ff8e-7f86-96ac-284b7f1ab001" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e6946-ff8e-7a58-ac3a-b7f75e611556" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-ff8e-7f86-96ac-284b7f1ab001" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_ScheduleOfMarketableSecuritiesLineItems_019e6946-ff8e-774b-98bd-5e75c0aff3c7" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYield_019e6946-ff8e-7bea-957b-375b871bf648" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYield_019e6946-ff8e-7bea-957b-375b871bf648" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesYearTwoThroughFiveAnnualizedAverageYield_019e6946-ff8e-7ac8-8d72-4c9bb7828bdb" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesYearTwoThroughFiveAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesYearTwoThroughFiveAnnualizedAverageYield_019e6946-ff8e-7ac8-8d72-4c9bb7828bdb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesYearSixThroughTenAnnualizedAverageYield_019e6946-ff8e-7622-b18c-c0c8af7dece9" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesYearSixThroughTenAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesYearSixThroughTenAnnualizedAverageYield_019e6946-ff8e-7622-b18c-c0c8af7dece9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAnnualizedAverageYield_019e6946-ff8e-7d9c-8d37-c3ff2e94c9ee" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAnnualizedAverageYield_019e6946-ff8e-7d9c-8d37-c3ff2e94c9ee" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYield_019e6946-ff8e-783e-bcf5-41e22c14ab4c" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYield_019e6946-ff8e-783e-bcf5-41e22c14ab4c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYield_019e6946-ff8e-79b6-80fc-f2249e87bb6e" xlink:href="ms-20260630.xsd#ms_HeldToMaturitySecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYield_019e6946-ff8e-79b6-80fc-f2249e87bb6e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesYearTwoThroughFiveAnnualizedAverageYield_019e6946-ff8e-7f57-be4a-b1ec549d034f" xlink:href="ms-20260630.xsd#ms_HeldToMaturitySecuritiesDebtMaturitiesYearTwoThroughFiveAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesYearTwoThroughFiveAnnualizedAverageYield_019e6946-ff8e-7f57-be4a-b1ec549d034f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesYearSixThroughTenAnnualizedAverageYield_019e6946-ff8e-7b8b-9c49-7ba1ef5d3c9e" xlink:href="ms-20260630.xsd#ms_HeldToMaturitySecuritiesDebtMaturitiesYearSixThroughTenAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesYearSixThroughTenAnnualizedAverageYield_019e6946-ff8e-7b8b-9c49-7ba1ef5d3c9e" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsAnnualizedAverageYield_019e6946-ff8e-7dec-98a4-27a919b5998b" xlink:href="ms-20260630.xsd#ms_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsAnnualizedAverageYield_019e6946-ff8e-7dec-98a4-27a919b5998b" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesAnnualizedAverageYield_019e6946-ff8e-7e05-8225-188601738aab" xlink:href="ms-20260630.xsd#ms_HeldToMaturitySecuritiesDebtMaturitiesAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_HeldToMaturitySecuritiesDebtMaturitiesAnnualizedAverageYield_019e6946-ff8e-7e05-8225-188601738aab" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentSecuritiesDebtMaturitiesAnnualizedAverageYield_019e6946-ff8e-7c7a-98bc-43b58732f7a0" xlink:href="ms-20260630.xsd#ms_InvestmentSecuritiesDebtMaturitiesAnnualizedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_InvestmentSecuritiesDebtMaturitiesAnnualizedAverageYield_019e6946-ff8e-7c7a-98bc-43b58732f7a0" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYieldIncludingTheInterestRateSwapAccrualOfRelatedHedges_019e6946-ff8e-7a5a-8bb4-9a12481abeb3" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYieldIncludingTheInterestRateSwapAccrualOfRelatedHedges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesNextTwelveMonthsAnnualizedAverageYieldIncludingTheInterestRateSwapAccrualOfRelatedHedges_019e6946-ff8e-7a5a-8bb4-9a12481abeb3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldIncludingTheInterestRateSwapAccrualOfRelatedHedges_019e6946-ff8e-7995-904f-f1cc407b9194" xlink:href="ms-20260630.xsd#ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldIncludingTheInterestRateSwapAccrualOfRelatedHedges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldFiscalYearMaturityAbstract_019e6946-ff8e-776d-8474-5e10a681c50c" xlink:to="loc_ms_AvailableForSaleSecuritiesDebtMaturitiesAnnualizedAverageYieldIncludingTheInterestRateSwapAccrualOfRelatedHedges_019e6946-ff8e-7995-904f-f1cc407b9194" xlink:type="arc" order="13"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/CollateralizedTransactionsGrossSecuredFinancingBalancesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#CollateralizedTransactionsGrossSecuredFinancingBalancesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/CollateralizedTransactionsGrossSecuredFinancingBalancesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesFinancingTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionTable_019e6946-ff8e-72ff-a1a5-6f83d1df2bd7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesFinancingTransactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionTable_019e6946-ff8e-72ff-a1a5-6f83d1df2bd7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_019e6946-ff8e-7f6f-a175-6c875a61309a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTable_019e6946-ff8e-72ff-a1a5-6f83d1df2bd7" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_019e6946-ff8e-7f6f-a175-6c875a61309a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7f6f-a175-6c875a61309a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_019e6946-ff8e-7f6f-a175-6c875a61309a" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7f6f-a175-6c875a61309a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7265-872f-a734c9ce8dcf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodsAxis_019e6946-ff8e-7f6f-a175-6c875a61309a" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7265-872f-a734c9ce8dcf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaturityOvernightMember_019e6946-ff8e-7d74-ace9-263f0ba0ae1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MaturityOvernightMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7265-872f-a734c9ce8dcf" xlink:to="loc_us-gaap_MaturityOvernightMember_019e6946-ff8e-7d74-ace9-263f0ba0ae1a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaturityUpTo30DaysMember_019e6946-ff8e-7ba5-a877-5b3ae7bda9d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MaturityUpTo30DaysMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7265-872f-a734c9ce8dcf" xlink:to="loc_us-gaap_MaturityUpTo30DaysMember_019e6946-ff8e-7ba5-a877-5b3ae7bda9d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Maturity30To90DaysMember_019e6946-ff8e-714f-afd8-53cc83fd6dcc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Maturity30To90DaysMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7265-872f-a734c9ce8dcf" xlink:to="loc_us-gaap_Maturity30To90DaysMember_019e6946-ff8e-714f-afd8-53cc83fd6dcc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaturityOver90DaysMember_019e6946-ff8e-79ba-b892-445b64c39c35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MaturityOver90DaysMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseMaturityPeriodDomain_019e6946-ff8e-7265-872f-a734c9ce8dcf" xlink:to="loc_us-gaap_MaturityOver90DaysMember_019e6946-ff8e-79ba-b892-445b64c39c35" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralAxis_019e6946-ff8e-7d87-9de9-1d6323923eaa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTable_019e6946-ff8e-72ff-a1a5-6f83d1df2bd7" xlink:to="loc_us-gaap_CollateralAxis_019e6946-ff8e-7d87-9de9-1d6323923eaa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_019e6946-ff8e-7d87-9de9-1d6323923eaa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CollateralAxis_019e6946-ff8e-7d87-9de9-1d6323923eaa" xlink:to="loc_us-gaap_CollateralDomain_019e6946-ff8e-7d87-9de9-1d6323923eaa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain_019e6946-ff8e-78b8-ad75-f1ba68464e0f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CollateralAxis_019e6946-ff8e-7d87-9de9-1d6323923eaa" xlink:to="loc_us-gaap_CollateralDomain_019e6946-ff8e-78b8-ad75-f1ba68464e0f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7131-8bb4-85dbb00f3b0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_019e6946-ff8e-78b8-ad75-f1ba68464e0f" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e6946-ff8e-7131-8bb4-85dbb00f3b0a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-ff8e-7931-adbd-0ac7d08af667" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_019e6946-ff8e-78b8-ad75-f1ba68464e0f" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_019e6946-ff8e-7931-adbd-0ac7d08af667" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CorporateEquitiesMember_019e6946-ff8e-7c7d-8d74-85aab46bc7ea" xlink:href="ms-20260630.xsd#ms_CorporateEquitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_019e6946-ff8e-78b8-ad75-f1ba68464e0f" xlink:to="loc_ms_CorporateEquitiesMember_019e6946-ff8e-7c7d-8d74-85aab46bc7ea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedSecuritiesOtherMember_019e6946-ff8e-7ed5-8074-2cc13b754a18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedSecuritiesOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CollateralDomain_019e6946-ff8e-78b8-ad75-f1ba68464e0f" xlink:to="loc_us-gaap_CollateralizedSecuritiesOtherMember_019e6946-ff8e-7ed5-8074-2cc13b754a18" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement_019e6946-ff8e-79b6-a45c-6756f6996361" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:to="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement_019e6946-ff8e-79b6-a45c-6756f6996361" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedGrossIncludingNotSubjectToMasterNettingArrangement_019e6946-ff8e-7802-99ed-d762b515e96c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesLoanedGrossIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:to="loc_us-gaap_SecuritiesLoanedGrossIncludingNotSubjectToMasterNettingArrangement_019e6946-ff8e-7802-99ed-d762b515e96c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesLoanedAndSecuritiesSoldUnderAgreementToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement_019e6946-ff8e-76e8-9fbc-400f198b78c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesLoanedAndSecuritiesSoldUnderAgreementToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:to="loc_us-gaap_SecuritiesLoanedAndSecuritiesSoldUnderAgreementToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement_019e6946-ff8e-76e8-9fbc-400f198b78c8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ObligationToReturnSecuritiesReceivedAsCollateral_019e6946-ff8e-76e4-8d5b-b111475b5fab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ObligationToReturnSecuritiesReceivedAsCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:to="loc_us-gaap_ObligationToReturnSecuritiesReceivedAsCollateral_019e6946-ff8e-76e4-8d5b-b111475b5fab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentRelatedLiabilities_019e6946-ff8e-710c-945f-2b59b3d4e405" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentRelatedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e6946-ff8e-775b-a539-89c52bf391eb" xlink:to="loc_us-gaap_InvestmentRelatedLiabilities_019e6946-ff8e-710c-945f-2b59b3d4e405" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/CollateralizedTransactionsAssetsLoanedorPledgedDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#CollateralizedTransactionsAssetsLoanedorPledgedDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/CollateralizedTransactionsAssetsLoanedorPledgedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralLineItems_019e6946-ff8e-762e-b159-01c647d349fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralTable_019e6946-ff8e-790f-8337-21b20a4032bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralLineItems_019e6946-ff8e-762e-b159-01c647d349fc" xlink:to="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralTable_019e6946-ff8e-790f-8337-21b20a4032bc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusAxis_019e6946-ff8e-7815-8482-6a80119c441c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralTable_019e6946-ff8e-790f-8337-21b20a4032bc" xlink:to="loc_us-gaap_PledgedStatusAxis_019e6946-ff8e-7815-8482-6a80119c441c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusDomain_019e6946-ff8e-7815-8482-6a80119c441c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PledgedStatusAxis_019e6946-ff8e-7815-8482-6a80119c441c" xlink:to="loc_us-gaap_PledgedStatusDomain_019e6946-ff8e-7815-8482-6a80119c441c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusDomain_019e6946-ff8e-75ca-8822-7043d2f80f64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PledgedStatusAxis_019e6946-ff8e-7815-8482-6a80119c441c" xlink:to="loc_us-gaap_PledgedStatusDomain_019e6946-ff8e-75ca-8822-7043d2f80f64" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetPledgedAsCollateralWithoutRightMember_019e6946-ff8e-7921-af89-65eeb07a6d77" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetPledgedAsCollateralWithoutRightMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PledgedStatusDomain_019e6946-ff8e-75ca-8822-7043d2f80f64" xlink:to="loc_us-gaap_AssetPledgedAsCollateralWithoutRightMember_019e6946-ff8e-7921-af89-65eeb07a6d77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsOwnedPledgedStatusExtensibleEnumeration_019e6946-ff8e-75ef-9174-c74afcffd0cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsOwnedPledgedStatusExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralLineItems_019e6946-ff8e-762e-b159-01c647d349fc" xlink:to="loc_us-gaap_FinancialInstrumentsOwnedPledgedStatusExtensibleEnumeration_019e6946-ff8e-75ef-9174-c74afcffd0cd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TradingAssetsFairValueDisclosure_019e6946-ff8e-702d-ad50-9dc0d6e45b6e" xlink:href="ms-20260630.xsd#ms_TradingAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralLineItems_019e6946-ff8e-762e-b159-01c647d349fc" xlink:to="loc_ms_TradingAssetsFairValueDisclosure_019e6946-ff8e-702d-ad50-9dc0d6e45b6e" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansbyTypeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansbyTypeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansbyTypeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-7375-a8c3-0900922a3c84" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7211-9717-3ad491ea4c13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-7375-a8c3-0900922a3c84" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7211-9717-3ad491ea4c13" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7bfc-b0a9-8e1c7870e97d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7211-9717-3ad491ea4c13" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7bfc-b0a9-8e1c7870e97d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7bfc-b0a9-8e1c7870e97d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7bfc-b0a9-8e1c7870e97d" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7bfc-b0a9-8e1c7870e97d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7bfc-b0a9-8e1c7870e97d" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-730e-8e0d-044a878f6c61" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-730e-8e0d-044a878f6c61" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7bc7-ab78-bee1865652e5" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7bc7-ab78-bee1865652e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7f37-b839-d574e7e42caa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7f37-b839-d574e7e42caa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7211-8e2c-c7eaf4ef1935" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7211-8e2c-c7eaf4ef1935" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7a4b-936f-42a878f774e4" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7660-9857-1cb5686ac1ff" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7a4b-936f-42a878f774e4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionAxis_019e6946-ff8e-7f2b-8330-4e180f55a40b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicDistributionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7211-9717-3ad491ea4c13" xlink:to="loc_us-gaap_GeographicDistributionAxis_019e6946-ff8e-7f2b-8330-4e180f55a40b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionDomain_019e6946-ff8e-7f2b-8330-4e180f55a40b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicDistributionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GeographicDistributionAxis_019e6946-ff8e-7f2b-8330-4e180f55a40b" xlink:to="loc_us-gaap_GeographicDistributionDomain_019e6946-ff8e-7f2b-8330-4e180f55a40b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionDomain_019e6946-ff8e-73ce-b84b-fe78bb2b9f72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicDistributionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GeographicDistributionAxis_019e6946-ff8e-7f2b-8330-4e180f55a40b" xlink:to="loc_us-gaap_GeographicDistributionDomain_019e6946-ff8e-73ce-b84b-fe78bb2b9f72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicDistributionForeignMember_019e6946-ff8e-77d7-9e5c-82a609dd3592" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicDistributionForeignMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GeographicDistributionDomain_019e6946-ff8e-73ce-b84b-fe78bb2b9f72" xlink:to="loc_us-gaap_GeographicDistributionForeignMember_019e6946-ff8e-77d7-9e5c-82a609dd3592" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableNetAbstract_019e6946-ff8e-7a60-b215-05668ac75cf3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotesReceivableNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-7375-a8c3-0900922a3c84" xlink:to="loc_us-gaap_NotesReceivableNetAbstract_019e6946-ff8e-7a60-b215-05668ac75cf3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-781f-b517-681cc68e1434" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotesReceivableNetAbstract_019e6946-ff8e-7a60-b215-05668ac75cf3" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-781f-b517-681cc68e1434" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-7f72-b6cb-5ca9a364303c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotesReceivableNetAbstract_019e6946-ff8e-7a60-b215-05668ac75cf3" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-7f72-b6cb-5ca9a364303c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-ff8e-7f7c-8e44-4ac55ad91488" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NotesReceivableNetAbstract_019e6946-ff8e-7a60-b215-05668ac75cf3" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e6946-ff8e-7f7c-8e44-4ac55ad91488" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesHeldForSaleAbstract_019e6946-ff8e-7a68-998d-c9b7e8e92a49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivablesHeldForSaleAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-7375-a8c3-0900922a3c84" xlink:to="loc_us-gaap_ReceivablesHeldForSaleAbstract_019e6946-ff8e-7a68-998d-c9b7e8e92a49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount_019e6946-ff8e-7c88-94dc-a7d2a7988964" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReceivablesHeldForSaleAbstract_019e6946-ff8e-7a68-998d-c9b7e8e92a49" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleAmount_019e6946-ff8e-7c88-94dc-a7d2a7988964" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup_019e6946-ff8e-767c-bb56-25d0ced50cf6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReceivablesHeldForSaleAbstract_019e6946-ff8e-7a68-998d-c9b7e8e92a49" xlink:to="loc_us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup_019e6946-ff8e-767c-bb56-25d0ced50cf6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_019e6946-ff8e-7285-892b-2f3deba165da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-7375-a8c3-0900922a3c84" xlink:to="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_019e6946-ff8e-7285-892b-2f3deba165da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableIncludingHeldForSaleBeforeAllowanceForCreditLoss_019e6946-ff8e-774b-ab6b-7fc8587e4f2c" xlink:href="ms-20260630.xsd#ms_FinancingReceivableIncludingHeldForSaleBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_019e6946-ff8e-7285-892b-2f3deba165da" xlink:to="loc_ms_FinancingReceivableIncludingHeldForSaleBeforeAllowanceForCreditLoss_019e6946-ff8e-774b-ab6b-7fc8587e4f2c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-7af2-8d02-7dec6ec1accb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableIncludingHeldForSaleAfterAllowanceForCreditLoss_019e6946-ff8e-7680-8226-2e2d85ecc39b" xlink:href="ms-20260630.xsd#ms_FinancingReceivableIncludingHeldForSaleAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_019e6946-ff8e-7285-892b-2f3deba165da" xlink:to="loc_ms_FinancingReceivableIncludingHeldForSaleAfterAllowanceForCreditLoss_019e6946-ff8e-7680-8226-2e2d85ecc39b" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansbyInterestRateTypeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansbyInterestRateTypeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansbyInterestRateTypeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71d5-9205-15b8a74b2891" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-733c-bc08-91d056760e05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71d5-9205-15b8a74b2891" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-733c-bc08-91d056760e05" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cc5-b3eb-dc8a1b59ff84" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-733c-bc08-91d056760e05" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cc5-b3eb-dc8a1b59ff84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7cc5-b3eb-dc8a1b59ff84_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cc5-b3eb-dc8a1b59ff84" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7cc5-b3eb-dc8a1b59ff84_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cc5-b3eb-dc8a1b59ff84" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-73e4-a45e-1a0750f33cd0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-73e4-a45e-1a0750f33cd0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-764c-89ed-61d337ac3702" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-764c-89ed-61d337ac3702" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7a6f-8722-398025f33b0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7a6f-8722-398025f33b0c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7c7c-9786-9f189c4c3848" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7c7c-9786-9f189c4c3848" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-76c9-91ee-f5e5d062c10d" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-76ee-80d5-02eb95fd91ba" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-76c9-91ee-f5e5d062c10d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableIncludingHeldForSaleWithFixedRatesOfInterest_019e6946-ff8e-7362-929a-d2504b69ce72" xlink:href="ms-20260630.xsd#ms_FinancingReceivableIncludingHeldForSaleWithFixedRatesOfInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71d5-9205-15b8a74b2891" xlink:to="loc_ms_FinancingReceivableIncludingHeldForSaleWithFixedRatesOfInterest_019e6946-ff8e-7362-929a-d2504b69ce72" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableIncludingHeldForSaleWithVariableRatesOfInterest_019e6946-ff8e-77f2-995f-afcd90bad9dd" xlink:href="ms-20260630.xsd#ms_FinancingReceivableIncludingHeldForSaleWithVariableRatesOfInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71d5-9205-15b8a74b2891" xlink:to="loc_ms_FinancingReceivableIncludingHeldForSaleWithVariableRatesOfInterest_019e6946-ff8e-77f2-995f-afcd90bad9dd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansHeldforInvestmentbeforeAllowancebyCreditQualityandOriginationYearDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansHeldforInvestmentbeforeAllowancebyCreditQualityandOriginationYearDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesLoansHeldforInvestmentbeforeAllowancebyCreditQualityandOriginationYearDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-72e5-93ab-36729a341411" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-72e5-93ab-36729a341411" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7c4e-86dd-aad0f5d5a666" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-72e5-93ab-36729a341411" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7c4e-86dd-aad0f5d5a666" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7c4e-86dd-aad0f5d5a666_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7c4e-86dd-aad0f5d5a666" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7c4e-86dd-aad0f5d5a666_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7c4e-86dd-aad0f5d5a666" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7177-bc1d-2e1a91240321" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7177-bc1d-2e1a91240321" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-75db-af4c-ee2ccbba89ed" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-75db-af4c-ee2ccbba89ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7fb5-a189-ed68cfe905f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7fb5-a189-ed68cfe905f3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7315-af7e-19c5a4ab8702" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7315-af7e-19c5a4ab8702" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7e53-978c-f6f84348434e" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7a3b-8bdc-65fea25f99b2" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7e53-978c-f6f84348434e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingMember_019e6946-ff8e-7953-a524-a5642590f975" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7e53-978c-f6f84348434e" xlink:to="loc_ms_SecuritiesBasedLendingMember_019e6946-ff8e-7953-a524-a5642590f975" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherLoansMember_019e6946-ff8e-786c-98ec-c9cb15d3d53c" xlink:href="ms-20260630.xsd#ms_OtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7e53-978c-f6f84348434e" xlink:to="loc_ms_OtherLoansMember_019e6946-ff8e-786c-98ec-c9cb15d3d53c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7c61-a147-76f5451e6ea0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-72e5-93ab-36729a341411" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7c61-a147-76f5451e6ea0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7c61-a147-76f5451e6ea0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7c61-a147-76f5451e6ea0" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7c61-a147-76f5451e6ea0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7009-84c6-338f5ec81da6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8e-7c61-a147-76f5451e6ea0" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7009-84c6-338f5ec81da6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8e-70a8-b2d1-7467b7aa3ee8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7009-84c6-338f5ec81da6" xlink:to="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8e-70a8-b2d1-7467b7aa3ee8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8e-7efb-9d09-cde17f92b584" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalNoninvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8e-7009-84c6-338f5ec81da6" xlink:to="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8e-7efb-9d09-cde17f92b584" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditScoreFicoAxis_019e6946-ff8e-7815-ad7a-e966b4152ee0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditScoreFicoAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-72e5-93ab-36729a341411" xlink:to="loc_us-gaap_CreditScoreFicoAxis_019e6946-ff8e-7815-ad7a-e966b4152ee0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-7815-ad7a-e966b4152ee0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditScoreFicoDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditScoreFicoAxis_019e6946-ff8e-7815-ad7a-e966b4152ee0" xlink:to="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-7815-ad7a-e966b4152ee0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-705b-a046-1f65d0573236" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditScoreFicoDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditScoreFicoAxis_019e6946-ff8e-7815-ad7a-e966b4152ee0" xlink:to="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-705b-a046-1f65d0573236" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FICOScoreGreaterthanorEqualto740Member_019e6946-ff8e-7974-a518-398278c1f8df" xlink:href="ms-20260630.xsd#ms_FICOScoreGreaterthanorEqualto740Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-705b-a046-1f65d0573236" xlink:to="loc_ms_FICOScoreGreaterthanorEqualto740Member_019e6946-ff8e-7974-a518-398278c1f8df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FICOScoreBetween680and739Member_019e6946-ff8e-77fa-9607-c59075d017c6" xlink:href="ms-20260630.xsd#ms_FICOScoreBetween680and739Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-705b-a046-1f65d0573236" xlink:to="loc_ms_FICOScoreBetween680and739Member_019e6946-ff8e-77fa-9607-c59075d017c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FICOScoreLessthan680Member_019e6946-ff8e-7940-bd19-d25e36f0fd50" xlink:href="ms-20260630.xsd#ms_FICOScoreLessthan680Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditScoreFicoDomain_019e6946-ff8e-705b-a046-1f65d0573236" xlink:to="loc_ms_FICOScoreLessthan680Member_019e6946-ff8e-7940-bd19-d25e36f0fd50" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanToValueAxis_019e6946-ff8e-7361-8671-bc8975b3c09b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanToValueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-72e5-93ab-36729a341411" xlink:to="loc_us-gaap_LoanToValueAxis_019e6946-ff8e-7361-8671-bc8975b3c09b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanToValueDomain_019e6946-ff8e-7361-8671-bc8975b3c09b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanToValueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LoanToValueAxis_019e6946-ff8e-7361-8671-bc8975b3c09b" xlink:to="loc_us-gaap_LoanToValueDomain_019e6946-ff8e-7361-8671-bc8975b3c09b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanToValueDomain_019e6946-ff8e-73bd-b4e1-2cb4bcef908f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanToValueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LoanToValueAxis_019e6946-ff8e-7361-8671-bc8975b3c09b" xlink:to="loc_us-gaap_LoanToValueDomain_019e6946-ff8e-73bd-b4e1-2cb4bcef908f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebttoValueRatioLessthanorEqualto80PercentMember_019e6946-ff8e-74cd-95ce-14b0d80fe561" xlink:href="ms-20260630.xsd#ms_DebttoValueRatioLessthanorEqualto80PercentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanToValueDomain_019e6946-ff8e-73bd-b4e1-2cb4bcef908f" xlink:to="loc_ms_DebttoValueRatioLessthanorEqualto80PercentMember_019e6946-ff8e-74cd-95ce-14b0d80fe561" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebttoValueRatioGreaterthan80PercentMember_019e6946-ff8e-7659-afe5-80288be4178c" xlink:href="ms-20260630.xsd#ms_DebttoValueRatioGreaterthan80PercentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanToValueDomain_019e6946-ff8e-73bd-b4e1-2cb4bcef908f" xlink:to="loc_ms_DebttoValueRatioGreaterthan80PercentMember_019e6946-ff8e-7659-afe5-80288be4178c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolving_019e6946-ff8e-755e-bd3a-e5ff2f092f27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestRevolving"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolving_019e6946-ff8e-755e-bd3a-e5ff2f092f27" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear_019e6946-ff8e-7f6d-aa93-e5f136e64d0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear_019e6946-ff8e-7f6d-aa93-e5f136e64d0b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear_019e6946-ff8e-778f-9dc2-db7a69983045" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear_019e6946-ff8e-778f-9dc2-db7a69983045" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear_019e6946-ff8e-7a14-b699-fe809bfedfbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear_019e6946-ff8e-7a14-b699-fe809bfedfbc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear_019e6946-ff8e-73a2-ac0d-0f717dec0111" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear_019e6946-ff8e-73a2-ac0d-0f717dec0111" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear_019e6946-ff8e-7a11-966c-4b8c89389c26" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear_019e6946-ff8e-7a11-966c-4b8c89389c26" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear_019e6946-ff8e-7d58-950d-2f1c46cbf4c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear_019e6946-ff8e-7d58-950d-2f1c46cbf4c6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-7bf8-8850-6b6f6eda2c42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-73ce-8360-91107573fb56" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-7bf8-8850-6b6f6eda2c42" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesPastDueLoansHeldforInvestmentbeforeAllowanceDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesPastDueLoansHeldforInvestmentbeforeAllowanceDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesPastDueLoansHeldforInvestmentbeforeAllowanceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e8-a83b-9c7bbfdb7041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-730f-8415-79cf4cc59911" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e8-a83b-9c7bbfdb7041" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-730f-8415-79cf4cc59911" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77c5-871f-1e43ffa84581" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-730f-8415-79cf4cc59911" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77c5-871f-1e43ffa84581" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-77c5-871f-1e43ffa84581_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77c5-871f-1e43ffa84581" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-77c5-871f-1e43ffa84581_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7145-ba31-e39de3a0d326" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77c5-871f-1e43ffa84581" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7145-ba31-e39de3a0d326" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7341-bd2d-0caccb8a6355" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7145-ba31-e39de3a0d326" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7341-bd2d-0caccb8a6355" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7c1f-84f9-e1d55977f72d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7145-ba31-e39de3a0d326" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7c1f-84f9-e1d55977f72d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7039-884c-b07c0d5f0689" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7145-ba31-e39de3a0d326" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7039-884c-b07c0d5f0689" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7a8b-a194-2fca2e4c6601" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-730f-8415-79cf4cc59911" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7a8b-a194-2fca2e4c6601" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7a8b-a194-2fca2e4c6601_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7a8b-a194-2fca2e4c6601" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7a8b-a194-2fca2e4c6601_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-70d2-85d0-208e40b291fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7a8b-a194-2fca2e4c6601" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-70d2-85d0-208e40b291fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancialAssetPastDueMinusCurrentMember_019e6946-ff8e-7857-af59-0fa72f258a4e" xlink:href="ms-20260630.xsd#ms_FinancialAssetPastDueMinusCurrentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-70d2-85d0-208e40b291fa" xlink:to="loc_ms_FinancialAssetPastDueMinusCurrentMember_019e6946-ff8e-7857-af59-0fa72f258a4e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-7acd-ae46-89eac067bcde" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e8-a83b-9c7bbfdb7041" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-7acd-ae46-89eac067bcde" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesNonaccrualLoansHeldforInvestmentbeforeAllowanceDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesNonaccrualLoansHeldforInvestmentbeforeAllowanceDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesNonaccrualLoansHeldforInvestmentbeforeAllowanceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e5-aadd-f6b800d6398a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7c0c-b4fc-a4e32fe23567" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e5-aadd-f6b800d6398a" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7c0c-b4fc-a4e32fe23567" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-73df-86ca-eb420428a188" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e6946-ff8e-7c0c-b4fc-a4e32fe23567" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-73df-86ca-eb420428a188" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-73df-86ca-eb420428a188_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-73df-86ca-eb420428a188" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-73df-86ca-eb420428a188_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-73df-86ca-eb420428a188" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7f63-9796-42aad1bf5868" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7f63-9796-42aad1bf5868" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7835-8411-3af6e2b933ae" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7835-8411-3af6e2b933ae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-766f-9170-8f87fc1cf787" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-766f-9170-8f87fc1cf787" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7cff-bf98-d966a18670b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7cff-bf98-d966a18670b5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-70b2-bec8-dda793b2fe33" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7016-af2c-97b837d9c8ff" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-70b2-bec8-dda793b2fe33" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_019e6946-ff8e-7457-bdd3-a9ed1f5e5a3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e5-aadd-f6b800d6398a" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_019e6946-ff8e-7457-bdd3-a9ed1f5e5a3a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance_019e6946-ff8e-7bca-8b0d-8cacd0c41e15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e6946-ff8e-71e5-aadd-f6b800d6398a" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance_019e6946-ff8e-7bca-8b0d-8cacd0c41e15" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesModifiedLoansHeldforInvestmentDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesModifiedLoansHeldforInvestmentDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesModifiedLoansHeldforInvestmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7292-845e-809b4ef6b5d7" xlink:href="ms-20260630.xsd#ms_FinancingReceivableModifiedLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-700b-b79c-687ad1b47dbc" xlink:href="ms-20260630.xsd#ms_FinancingReceivableModifiedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7292-845e-809b4ef6b5d7" xlink:to="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-700b-b79c-687ad1b47dbc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77ed-a91e-cfc5e865c46d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-700b-b79c-687ad1b47dbc" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77ed-a91e-cfc5e865c46d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-77ed-a91e-cfc5e865c46d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77ed-a91e-cfc5e865c46d" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-77ed-a91e-cfc5e865c46d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7ed8-bdba-fbe0f3db1644" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-77ed-a91e-cfc5e865c46d" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7ed8-bdba-fbe0f3db1644" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-743f-a635-464821b6536a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7ed8-bdba-fbe0f3db1644" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-743f-a635-464821b6536a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7211-9054-022584a79eb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7ed8-bdba-fbe0f3db1644" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7211-9054-022584a79eb4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7785-b967-763df395235d" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7ed8-bdba-fbe0f3db1644" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7785-b967-763df395235d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7e74-a8e2-291ed757caae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7ed8-bdba-fbe0f3db1644" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7e74-a8e2-291ed757caae" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationAxis_019e6946-ff8e-7e50-aa58-235690e4b9a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-700b-b79c-687ad1b47dbc" xlink:to="loc_us-gaap_LoanRestructuringModificationAxis_019e6946-ff8e-7e50-aa58-235690e4b9a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7e50-aa58-235690e4b9a4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LoanRestructuringModificationAxis_019e6946-ff8e-7e50-aa58-235690e4b9a4" xlink:to="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7e50-aa58-235690e4b9a4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LoanRestructuringModificationAxis_019e6946-ff8e-7e50-aa58-235690e4b9a4" xlink:to="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtendedMaturityMember_019e6946-ff8e-77b1-a637-709d36c09db4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExtendedMaturityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:to="loc_us-gaap_ExtendedMaturityMember_019e6946-ff8e-77b1-a637-709d36c09db4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentDeferralMember_019e6946-ff8e-723d-9950-28861fdaf1bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentDeferralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:to="loc_us-gaap_PaymentDeferralMember_019e6946-ff8e-723d-9950-28861fdaf1bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember_019e7552-cd85-723c-89de-638afbba889f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExtendedMaturityAndInterestRateReductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:to="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember_019e7552-cd85-723c-89de-638afbba889f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrincipalForgivenessMember_019e6946-ff8e-7f22-95c0-50523f54645d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrincipalForgivenessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:to="loc_us-gaap_PrincipalForgivenessMember_019e6946-ff8e-7f22-95c0-50523f54645d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractualInterestRateReductionMember_019e6946-ff8e-753d-b2da-8e2a0d6a4636" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractualInterestRateReductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e6946-ff8e-7426-bdfc-37006901677c" xlink:to="loc_us-gaap_ContractualInterestRateReductionMember_019e6946-ff8e-753d-b2da-8e2a0d6a4636" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationNameAxis_019e6946-ff8e-76ef-9021-7ed78411768f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-700b-b79c-687ad1b47dbc" xlink:to="loc_us-gaap_LoanRestructuringModificationNameAxis_019e6946-ff8e-76ef-9021-7ed78411768f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationNameDomain_019e6946-ff8e-76ef-9021-7ed78411768f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LoanRestructuringModificationNameAxis_019e6946-ff8e-76ef-9021-7ed78411768f" xlink:to="loc_us-gaap_LoanRestructuringModificationNameDomain_019e6946-ff8e-76ef-9021-7ed78411768f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationNameDomain_019e6946-ff8e-7741-85af-c174247a862c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LoanRestructuringModificationNameAxis_019e6946-ff8e-76ef-9021-7ed78411768f" xlink:to="loc_us-gaap_LoanRestructuringModificationNameDomain_019e6946-ff8e-7741-85af-c174247a862c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SingleModificationsMember_019e6946-ff8e-706a-a17a-a9bc9f379f3f" xlink:href="ms-20260630.xsd#ms_SingleModificationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationNameDomain_019e6946-ff8e-7741-85af-c174247a862c" xlink:to="loc_ms_SingleModificationsMember_019e6946-ff8e-706a-a17a-a9bc9f379f3f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember_019e750d-2532-78e3-a023-9d8ff3dd0b35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExtendedMaturityAndInterestRateReductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationNameDomain_019e6946-ff8e-7741-85af-c174247a862c" xlink:to="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember_019e750d-2532-78e3-a023-9d8ff3dd0b35" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod_019e6946-ff8e-7042-8efc-e41173c83d03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7292-845e-809b4ef6b5d7" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod_019e6946-ff8e-7042-8efc-e41173c83d03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent_019e6946-ff8e-760d-b51a-d5ce235528a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7292-845e-809b4ef6b5d7" xlink:to="loc_us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent_019e6946-ff8e-760d-b51a-d5ce235528a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification_019e6946-ff8e-7f05-a050-97ed034a3031" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7292-845e-809b4ef6b5d7" xlink:to="loc_us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification_019e6946-ff8e-7f05-a050-97ed034a3031" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesPastDueLoansHeldforInvestmentModifiedintheLast12MonthsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesPastDueLoansHeldforInvestmentModifiedintheLast12MonthsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesPastDueLoansHeldforInvestmentModifiedintheLast12MonthsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModifiedSubsequentDefaultLineItems_019e6946-ff8e-7161-a22e-3fafaf3f6867" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableModifiedSubsequentDefaultLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-75aa-9454-7b29e997bafd" xlink:href="ms-20260630.xsd#ms_FinancingReceivableModifiedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableModifiedSubsequentDefaultLineItems_019e6946-ff8e-7161-a22e-3fafaf3f6867" xlink:to="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-75aa-9454-7b29e997bafd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7715-85c2-d8f4e38dbc84" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-75aa-9454-7b29e997bafd" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7715-85c2-d8f4e38dbc84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7715-85c2-d8f4e38dbc84_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7715-85c2-d8f4e38dbc84" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7715-85c2-d8f4e38dbc84_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7715-85c2-d8f4e38dbc84" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7060-8b88-6ac7a78b67f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7060-8b88-6ac7a78b67f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-716d-8790-e76a8d5dd74a" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-716d-8790-e76a8d5dd74a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-766c-96a7-69932f16026e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-766c-96a7-69932f16026e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7026-9a66-419aa61e0bef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7026-9a66-419aa61e0bef" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7b75-9f27-4dfa649a8a6a" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70a8-887a-609ab1c03464" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7b75-9f27-4dfa649a8a6a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7e58-93be-dcb4e22795c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-75aa-9454-7b29e997bafd" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7e58-93be-dcb4e22795c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7e58-93be-dcb4e22795c9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7e58-93be-dcb4e22795c9" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7e58-93be-dcb4e22795c9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-71e8-9210-9097167ad725" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-7e58-93be-dcb4e22795c9" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-71e8-9210-9097167ad725" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetPastDueMember_019e6946-ff8e-7e0b-bb21-c4a5a9d0e057" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-71e8-9210-9097167ad725" xlink:to="loc_us-gaap_FinancialAssetPastDueMember_019e6946-ff8e-7e0b-bb21-c4a5a9d0e057" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember_019e6946-ff8e-7339-829c-b4c084b68a42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialAssetPastDueMember_019e6946-ff8e-7e0b-bb21-c4a5a9d0e057" xlink:to="loc_us-gaap_FinancialAssetNotPastDueMember_019e6946-ff8e-7339-829c-b4c084b68a42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancialAsset30To89DaysPastDueMember_019e6946-ff8e-7d38-8bfe-aabf9b495fe1" xlink:href="ms-20260630.xsd#ms_FinancialAsset30To89DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialAssetPastDueMember_019e6946-ff8e-7e0b-bb21-c4a5a9d0e057" xlink:to="loc_ms_FinancialAsset30To89DaysPastDueMember_019e6946-ff8e-7d38-8bfe-aabf9b495fe1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancialAsset90DaysPastDueMember_019e6946-ff8e-7e02-a8b4-1c676567109f" xlink:href="ms-20260630.xsd#ms_FinancialAsset90DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialAssetPastDueMember_019e6946-ff8e-7e0b-bb21-c4a5a9d0e057" xlink:to="loc_ms_FinancialAsset90DaysPastDueMember_019e6946-ff8e-7e02-a8b4-1c676567109f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-7091-86f9-a1b46c9360e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModifiedSubsequentDefaultLineItems_019e6946-ff8e-7161-a22e-3fafaf3f6867" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e6946-ff8e-7091-86f9-a1b46c9360e1" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesNarrativeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7e66-baa2-9ad9fd11f9dc" xlink:href="ms-20260630.xsd#ms_FinancingReceivableModifiedLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-7c01-a105-eb07e34cc6fd" xlink:href="ms-20260630.xsd#ms_FinancingReceivableModifiedTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7e66-baa2-9ad9fd11f9dc" xlink:to="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-7c01-a105-eb07e34cc6fd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-705e-9b76-a480dc00d945" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_FinancingReceivableModifiedTable_019e6946-ff8e-7c01-a105-eb07e34cc6fd" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-705e-9b76-a480dc00d945" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-705e-9b76-a480dc00d945_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-705e-9b76-a480dc00d945" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-705e-9b76-a480dc00d945_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7fcd-8ee5-2677b15c140b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e6946-ff8e-705e-9b76-a480dc00d945" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7fcd-8ee5-2677b15c140b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancialAsset90DaysPastDueMember_019e6946-ff8e-7d8d-a5cc-71a719d8b1aa" xlink:href="ms-20260630.xsd#ms_FinancialAsset90DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e6946-ff8e-7fcd-8ee5-2677b15c140b" xlink:to="loc_ms_FinancialAsset90DaysPastDueMember_019e6946-ff8e-7d8d-a5cc-71a719d8b1aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableExcludingAccruedInterestNumberOfDefaultedAndModifiedInvestments_019e6946-ff8e-780a-b4ca-8cc7902cca90" xlink:href="ms-20260630.xsd#ms_FinancingReceivableExcludingAccruedInterestNumberOfDefaultedAndModifiedInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_FinancingReceivableModifiedLineItems_019e6946-ff8e-7e66-baa2-9ad9fd11f9dc" xlink:to="loc_ms_FinancingReceivableExcludingAccruedInterestNumberOfDefaultedAndModifiedInvestments_019e6946-ff8e-780a-b4ca-8cc7902cca90" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesAllowanceforCreditLossesRollforwardLoansandLendingCommitmentsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesAllowanceforCreditLossesRollforwardLoansandLendingCommitmentsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesAllowanceforCreditLossesRollforwardLoansandLendingCommitmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-7a13-b106-964617c37308" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e6946-ff8e-712b-b71b-bd70798e3a03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-7a13-b106-964617c37308" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e6946-ff8e-712b-b71b-bd70798e3a03" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-721d-a757-2f829e4e0d17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e6946-ff8e-712b-b71b-bd70798e3a03" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-721d-a757-2f829e4e0d17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-721d-a757-2f829e4e0d17_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-721d-a757-2f829e4e0d17" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-721d-a757-2f829e4e0d17_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-721d-a757-2f829e4e0d17" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7c72-a1dc-4eda5961a27c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-7c72-a1dc-4eda5961a27c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7863-bfb0-94c4cfdc1248" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7863-bfb0-94c4cfdc1248" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7bae-899b-eec8a8833416" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-7bae-899b-eec8a8833416" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7bbf-9ebc-6b17fad07c4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7bbf-9ebc-6b17fad07c4e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7193-ae44-9f91c6a644df" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7944-9b6d-3d10da886de3" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7193-ae44-9f91c6a644df" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForLoanAndLeaseLossesRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-7a13-b106-964617c37308" xlink:to="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-7706-b428-b19c18c75f3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-7706-b428-b19c18c75f3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_019e6946-ff8e-703c-87a1-b626fb0c8b8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_019e6946-ff8e-703c-87a1-b626fb0c8b8c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery_019e6946-ff8e-7975-a330-83fe6949b37a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery_019e6946-ff8e-7975-a330-83fe6949b37a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoffAfterRecovery_019e6946-ff8e-76c0-a430-920e92a8ffdc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoffAfterRecovery"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoffAfterRecovery_019e6946-ff8e-76c0-a430-920e92a8ffdc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal_019e6946-ff8e-7e7b-b27f-c30bd88f7e69" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal_019e6946-ff8e-7e7b-b27f-c30bd88f7e69" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossesOther_019e6946-ff8e-77b3-ba52-3ecdf5bc2559" xlink:href="ms-20260630.xsd#ms_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_ms_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossesOther_019e6946-ff8e-77b3-ba52-3ecdf5bc2559" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e6946-ff8e-7fd5-a57d-bfa5c1daaf67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableLoansHeldForInvestmentByLoanTypeToTotalLoansHeldForInvestmentPercent_019e6946-ff8e-76a9-a4f2-8748681ce784" xlink:href="ms-20260630.xsd#ms_FinancingReceivableLoansHeldForInvestmentByLoanTypeToTotalLoansHeldForInvestmentPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AllowanceForLoanAndLeaseLossesRollForward_019e6946-ff8e-787d-b79d-b1df2fc6a49d" xlink:to="loc_ms_FinancingReceivableLoansHeldForInvestmentByLoanTypeToTotalLoansHeldForInvestmentPercent_019e6946-ff8e-76a9-a4f2-8748681ce784" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward_019e6946-ff8e-7025-9511-13a4b3ec3612" xlink:href="ms-20260630.xsd#ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-7a13-b106-964617c37308" xlink:to="loc_ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward_019e6946-ff8e-7025-9511-13a4b3ec3612" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OffBalanceSheetAllowanceForCreditExposures_019e6946-ff8e-795a-a758-0d972ce23f6b" xlink:href="ms-20260630.xsd#ms_OffBalanceSheetAllowanceForCreditExposures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward_019e6946-ff8e-7025-9511-13a4b3ec3612" xlink:to="loc_ms_OffBalanceSheetAllowanceForCreditExposures_019e6946-ff8e-795a-a758-0d972ce23f6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_019e6946-ff8e-765d-a153-c28e88aad734" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward_019e6946-ff8e-7025-9511-13a4b3ec3612" xlink:to="loc_us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_019e6946-ff8e-765d-a153-c28e88aad734" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OffBalanceSheetCreditLossAllowanceForCreditExposuresOtherIncreaseDecrease_019e6946-ff8e-7b4e-8aed-16becbd10b78" xlink:href="ms-20260630.xsd#ms_OffBalanceSheetCreditLossAllowanceForCreditExposuresOtherIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward_019e6946-ff8e-7025-9511-13a4b3ec3612" xlink:to="loc_ms_OffBalanceSheetCreditLossAllowanceForCreditExposuresOtherIncreaseDecrease_019e6946-ff8e-7b4e-8aed-16becbd10b78" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OffBalanceSheetAllowanceForCreditExposures_019e6946-ff8e-7b8f-9b65-4f83dd2582f3" xlink:href="ms-20260630.xsd#ms_OffBalanceSheetAllowanceForCreditExposures"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AllowanceForCreditLossAndExposures_019e6946-ff8e-7f50-91e3-92734c519b6d" xlink:href="ms-20260630.xsd#ms_AllowanceForCreditLossAndExposures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_OffBalanceSheetLoanCommitmentsAllowanceForCreditExposuresRollForward_019e6946-ff8e-7025-9511-13a4b3ec3612" xlink:to="loc_ms_AllowanceForCreditLossAndExposures_019e6946-ff8e-7f50-91e3-92734c519b6d" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesGrossChargeoffsbyOriginationYearDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesGrossChargeoffsbyOriginationYearDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesGrossChargeoffsbyOriginationYearDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e6946-ff8e-7e2e-bb6e-38404f0851d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e6946-ff8e-7e2e-bb6e-38404f0851d2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cf2-9981-798a08185cc5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e6946-ff8e-7e2e-bb6e-38404f0851d2" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cf2-9981-798a08185cc5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7cf2-9981-798a08185cc5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cf2-9981-798a08185cc5" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-7cf2-9981-798a08185cc5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e6946-ff8e-7cf2-9981-798a08185cc5" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-72d1-bddb-1afd06faa5a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e6946-ff8e-72d1-bddb-1afd06faa5a6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7b9e-9c6b-86800e54994b" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-7b9e-9c6b-86800e54994b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-708a-b78e-d0085e1136d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialRealEstatePortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:to="loc_us-gaap_CommercialRealEstatePortfolioSegmentMember_019e6946-ff8e-708a-b78e-d0085e1136d3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7b32-b471-378b91a2a506" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e6946-ff8e-7b32-b471-378b91a2a506" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7c41-96c9-6a26642cd960" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e6946-ff8e-70d2-b3c3-1d7ea4e4224a" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-7c41-96c9-6a26642cd960" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRevolvingWriteoff_019e6946-ff8e-7929-a2ab-052cc173b999" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRevolvingWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:to="loc_us-gaap_FinancingReceivableRevolvingWriteoff_019e6946-ff8e-7929-a2ab-052cc173b999" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff_019e752a-17ea-7e66-a9a3-b467319d2637" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:to="loc_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff_019e752a-17ea-7e66-a9a3-b467319d2637" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableOriginatedMoreThanSixYearsBeforeCurrentFiscalYearWriteoff_019e752d-e410-733d-87b3-629a31be8146" xlink:href="ms-20260630.xsd#ms_FinancingReceivableOriginatedMoreThanSixYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:to="loc_ms_FinancingReceivableOriginatedMoreThanSixYearsBeforeCurrentFiscalYearWriteoff_019e752d-e410-733d-87b3-629a31be8146" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff_019e6946-ff8e-7c61-a894-92260d0a35ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:to="loc_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff_019e6946-ff8e-7c61-a894-92260d0a35ee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableAllowanceForCreditLossWriteoff_019e6946-ff8e-7be8-838f-c9e9077abe7c" xlink:href="ms-20260630.xsd#ms_FinancingReceivableAllowanceForCreditLossWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e6946-ff8e-749f-bd92-dd73c24d7410" xlink:to="loc_ms_FinancingReceivableAllowanceForCreditLossWriteoff_019e6946-ff8e-7be8-838f-c9e9077abe7c" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesEmployeeLoansDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#LoansLendingCommitmentsandRelatedAllowanceforCreditLossesEmployeeLoansDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/LoansLendingCommitmentsandRelatedAllowanceforCreditLossesEmployeeLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:href="ms-20260630.xsd#ms_EmployeeLoansLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ScheduleofEmployeeLoansTable_019e6946-ff8e-7eea-9547-0705ecbd9f24" xlink:href="ms-20260630.xsd#ms_ScheduleofEmployeeLoansTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:to="loc_ms_ScheduleofEmployeeLoansTable_019e6946-ff8e-7eea-9547-0705ecbd9f24" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_EmploymentStatusAxis_019e6946-ff8e-7c8b-bf4e-64c02e8ce706" xlink:href="ms-20260630.xsd#ms_EmploymentStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_ScheduleofEmployeeLoansTable_019e6946-ff8e-7eea-9547-0705ecbd9f24" xlink:to="loc_ms_EmploymentStatusAxis_019e6946-ff8e-7c8b-bf4e-64c02e8ce706" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_EmploymentStatusDomain_019e6946-ff8e-7c8b-bf4e-64c02e8ce706_default" xlink:href="ms-20260630.xsd#ms_EmploymentStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_EmploymentStatusAxis_019e6946-ff8e-7c8b-bf4e-64c02e8ce706" xlink:to="loc_ms_EmploymentStatusDomain_019e6946-ff8e-7c8b-bf4e-64c02e8ce706_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_EmploymentStatusDomain_019e6946-ff8e-70fb-a3ea-bf27686c598a" xlink:href="ms-20260630.xsd#ms_EmploymentStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_EmploymentStatusAxis_019e6946-ff8e-7c8b-bf4e-64c02e8ce706" xlink:to="loc_ms_EmploymentStatusDomain_019e6946-ff8e-70fb-a3ea-bf27686c598a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CurrentlyEmployedbytheFirmMember_019e6946-ff8e-7b16-b5cc-7145a99b3e04" xlink:href="ms-20260630.xsd#ms_CurrentlyEmployedbytheFirmMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmploymentStatusDomain_019e6946-ff8e-70fb-a3ea-bf27686c598a" xlink:to="loc_ms_CurrentlyEmployedbytheFirmMember_019e6946-ff8e-7b16-b5cc-7145a99b3e04" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NoLongerEmployedbytheFirmMember_019e6946-ff8e-7d13-8d3f-27ca28a2af25" xlink:href="ms-20260630.xsd#ms_NoLongerEmployedbytheFirmMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmploymentStatusDomain_019e6946-ff8e-70fb-a3ea-bf27686c598a" xlink:to="loc_ms_NoLongerEmployedbytheFirmMember_019e6946-ff8e-7d13-8d3f-27ca28a2af25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e6946-ff8e-7b60-b7c5-2f4c8faf72fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_ms_ScheduleofEmployeeLoansTable_019e6946-ff8e-7eea-9547-0705ecbd9f24" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e6946-ff8e-7b60-b7c5-2f4c8faf72fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019e6946-ff8e-7b60-b7c5-2f4c8faf72fd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e6946-ff8e-7b60-b7c5-2f4c8faf72fd" xlink:to="loc_us-gaap_RelatedPartyDomain_019e6946-ff8e-7b60-b7c5-2f4c8faf72fd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019e6946-ff8e-77b6-910f-7b1320bfc501" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e6946-ff8e-7b60-b7c5-2f4c8faf72fd" xlink:to="loc_us-gaap_RelatedPartyDomain_019e6946-ff8e-77b6-910f-7b1320bfc501" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019e6946-ff8e-70bc-a154-3dcd9d1efb70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019e6946-ff8e-77b6-910f-7b1320bfc501" xlink:to="loc_us-gaap_RelatedPartyMember_019e6946-ff8e-70bc-a154-3dcd9d1efb70" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_019e6946-ff8e-7dea-b82f-c66e48856e9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:to="loc_us-gaap_OtherReceivables_019e6946-ff8e-7dea-b82f-c66e48856e9e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DueFromEmployeesGross_019e6946-ff8e-7b5b-aef3-353a4b451e6f" xlink:href="ms-20260630.xsd#ms_DueFromEmployeesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:to="loc_ms_DueFromEmployeesGross_019e6946-ff8e-7b5b-aef3-353a4b451e6f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DueFromEmployeesAllowance_019e6946-ff8e-7e95-a7c2-d2b47ddb47b5" xlink:href="ms-20260630.xsd#ms_DueFromEmployeesAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:to="loc_ms_DueFromEmployeesAllowance_019e6946-ff8e-7e95-a7c2-d2b47ddb47b5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DueFromEmployeesNetOfAllowance_019e6946-ff8e-7eaf-ab31-6dcda0ea9938" xlink:href="ms-20260630.xsd#ms_DueFromEmployeesNetOfAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:to="loc_ms_DueFromEmployeesNetOfAllowance_019e6946-ff8e-7eaf-ab31-6dcda0ea9938" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DueFromEmployeesRepaymentTerms_019e6946-ff8e-7255-ab90-dbb5ad5c3fc6" xlink:href="ms-20260630.xsd#ms_DueFromEmployeesRepaymentTerms"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_EmployeeLoansLineItems_019e6946-ff8e-7c4d-85db-0cab36cfc4c4" xlink:to="loc_ms_DueFromEmployeesRepaymentTerms_019e6946-ff8e-7255-ab90-dbb5ad5c3fc6" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/OtherAssetsBalancesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#OtherAssetsBalancesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/OtherAssetsBalancesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-783c-a042-1790abaff37e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-7ad6-b266-4852ca4f8d04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-783c-a042-1790abaff37e" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-7ad6-b266-4852ca4f8d04" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6946-ff8e-7143-85d1-2b6cf1991909" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-7ad6-b266-4852ca4f8d04" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6946-ff8e-7143-85d1-2b6cf1991909" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6946-ff8e-7143-85d1-2b6cf1991909_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6946-ff8e-7143-85d1-2b6cf1991909" xlink:to="loc_us-gaap_SegmentDomain_019e6946-ff8e-7143-85d1-2b6cf1991909_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6946-ff8e-70d6-959d-af58c92a7703" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6946-ff8e-7143-85d1-2b6cf1991909" xlink:to="loc_us-gaap_SegmentDomain_019e6946-ff8e-70d6-959d-af58c92a7703" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentManagementSegmentMember_019e6946-ff8e-717c-9afa-6be3a994c078" xlink:href="ms-20260630.xsd#ms_InvestmentManagementSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6946-ff8e-70d6-959d-af58c92a7703" xlink:to="loc_ms_InvestmentManagementSegmentMember_019e6946-ff8e-717c-9afa-6be3a994c078" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e6946-ff8e-748a-bf75-6cf89da0b19d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-783c-a042-1790abaff37e" xlink:to="loc_us-gaap_EquityMethodInvestments_019e6946-ff8e-748a-bf75-6cf89da0b19d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6946-ff8e-7cb8-95d7-21e494821644" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-783c-a042-1790abaff37e" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6946-ff8e-7cb8-95d7-21e494821644" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/OtherAssetsJointVenturesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#OtherAssetsJointVenturesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/OtherAssetsJointVenturesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7b73-bd1f-88abcbe1c861" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-7bc7-86fb-a59a2f9c8885" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7b73-bd1f-88abcbe1c861" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-7bc7-86fb-a59a2f9c8885" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7aab-af94-476ccd82389c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-7bc7-86fb-a59a2f9c8885" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7aab-af94-476ccd82389c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-7aab-af94-476ccd82389c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7aab-af94-476ccd82389c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-7aab-af94-476ccd82389c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-712d-9379-af627452d6bf" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7aab-af94-476ccd82389c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-712d-9379-af627452d6bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MitsubishiUfjMorganStanleySecuritiesCoLtdMember_019e6946-ff8e-7c60-8327-6bc5ab7559f4" xlink:href="ms-20260630.xsd#ms_MitsubishiUfjMorganStanleySecuritiesCoLtdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-712d-9379-af627452d6bf" xlink:to="loc_ms_MitsubishiUfjMorganStanleySecuritiesCoLtdMember_019e6946-ff8e-7c60-8327-6bc5ab7559f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6946-ff8e-7d4d-bf87-e28fd1a97a43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7b73-bd1f-88abcbe1c861" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6946-ff8e-7d4d-bf87-e28fd1a97a43" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/OtherAssetsTaxEquityInvestmentsundertheProportionalAmortizationMethodDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#OtherAssetsTaxEquityInvestmentsundertheProportionalAmortizationMethodDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/OtherAssetsTaxEquityInvestmentsundertheProportionalAmortizationMethodDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7be9-9809-59e6d8e4fe6f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-772a-b2af-805271127b78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7be9-9809-59e6d8e4fe6f" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-772a-b2af-805271127b78" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7e10-a139-ede850b7da7f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6946-ff8e-772a-b2af-805271127b78" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7e10-a139-ede850b7da7f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-7e10-a139-ede850b7da7f_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7e10-a139-ede850b7da7f" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-7e10-a139-ede850b7da7f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-77a2-9c5e-cdbaf3bb73cc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6946-ff8e-7e10-a139-ede850b7da7f" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-77a2-9c5e-cdbaf3bb73cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LowIncomeHousingMember_019e6946-ff8e-7ab8-9a56-d6d1dd6045f7" xlink:href="ms-20260630.xsd#ms_LowIncomeHousingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-77a2-9c5e-cdbaf3bb73cc" xlink:to="loc_ms_LowIncomeHousingMember_019e6946-ff8e-7ab8-9a56-d6d1dd6045f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_RenewableEnergyAndOtherMember_019e6946-ff8e-74bd-8391-a85d207dc3ad" xlink:href="ms-20260630.xsd#ms_RenewableEnergyAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e6946-ff8e-77a2-9c5e-cdbaf3bb73cc" xlink:to="loc_ms_RenewableEnergyAndOtherMember_019e6946-ff8e-74bd-8391-a85d207dc3ad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationMethodQualifiedAffordableHousingProjectInvestments_019e6946-ff8e-7399-9dd9-069cfee44576" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationMethodQualifiedAffordableHousingProjectInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7be9-9809-59e6d8e4fe6f" xlink:to="loc_us-gaap_AmortizationMethodQualifiedAffordableHousingProjectInvestments_019e6946-ff8e-7399-9dd9-069cfee44576" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_QualifiedAffordableHousingProjectInvestmentsCommitment_019e6946-ff8e-76bd-bc85-1afa448cf0a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_QualifiedAffordableHousingProjectInvestmentsCommitment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7be9-9809-59e6d8e4fe6f" xlink:to="loc_us-gaap_QualifiedAffordableHousingProjectInvestmentsCommitment_019e6946-ff8e-76bd-bc85-1afa448cf0a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentProgramProportionalAmortizationMethodElectedCommitmentFundingPeriod_019e6946-ff8e-733e-92f1-d5b9769d14d9" xlink:href="ms-20260630.xsd#ms_InvestmentProgramProportionalAmortizationMethodElectedCommitmentFundingPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7be9-9809-59e6d8e4fe6f" xlink:to="loc_ms_InvestmentProgramProportionalAmortizationMethodElectedCommitmentFundingPeriod_019e6946-ff8e-733e-92f1-d5b9769d14d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentProportionalAmortizationMethodNotElectedAmount_019e6946-ff8e-707a-8ab5-3a2231a5d9d0" xlink:href="ms-20260630.xsd#ms_InvestmentProportionalAmortizationMethodNotElectedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6946-ff8e-7be9-9809-59e6d8e4fe6f" xlink:to="loc_ms_InvestmentProportionalAmortizationMethodNotElectedAmount_019e6946-ff8e-707a-8ab5-3a2231a5d9d0" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/CommitmentsGuaranteesandContingenciesCommitmentsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#CommitmentsGuaranteesandContingenciesCommitmentsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/CommitmentsGuaranteesandContingenciesCommitmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsLineItems_019e6946-ff8e-76a1-9311-7eb442bd4452" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsTable_019e6946-ff8e-767d-bf04-8d6412b23479" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_019e6946-ff8e-76a1-9311-7eb442bd4452" xlink:to="loc_us-gaap_OtherCommitmentsTable_019e6946-ff8e-767d-bf04-8d6412b23479" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-74be-b2fb-bc001b054337" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_019e6946-ff8e-767d-bf04-8d6412b23479" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-74be-b2fb-bc001b054337" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-74be-b2fb-bc001b054337_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-74be-b2fb-bc001b054337" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-74be-b2fb-bc001b054337_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7615-8282-9aabdb0c1a03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8e-74be-b2fb-bc001b054337" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7615-8282-9aabdb0c1a03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialLoanMember_019e6946-ff8e-7688-bab1-f0bc16d2c3c0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7615-8282-9aabdb0c1a03" xlink:to="loc_us-gaap_CommercialLoanMember_019e6946-ff8e-7688-bab1-f0bc16d2c3c0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-72f7-8fcb-91c7ff07631d" xlink:href="ms-20260630.xsd#ms_SecuredLendingFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7615-8282-9aabdb0c1a03" xlink:to="loc_ms_SecuredLendingFacilitiesMember_019e6946-ff8e-72f7-8fcb-91c7ff07631d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateMember_019e6946-ff8e-7481-8db5-fa6ea259f523" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7615-8282-9aabdb0c1a03" xlink:to="loc_us-gaap_RealEstateMember_019e6946-ff8e-7481-8db5-fa6ea259f523" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-79a0-85bd-d7bd856a4aad" xlink:href="ms-20260630.xsd#ms_SecuritiesBasedLendingandOtherLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8e-7615-8282-9aabdb0c1a03" xlink:to="loc_ms_SecuritiesBasedLendingandOtherLoansMember_019e6946-ff8e-79a0-85bd-d7bd856a4aad" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsAxis_019e6946-ff8e-7070-81e1-d4f58c86b2ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OtherCommitmentsTable_019e6946-ff8e-767d-bf04-8d6412b23479" xlink:to="loc_us-gaap_OtherCommitmentsAxis_019e6946-ff8e-7070-81e1-d4f58c86b2ce" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-7070-81e1-d4f58c86b2ce_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_OtherCommitmentsAxis_019e6946-ff8e-7070-81e1-d4f58c86b2ce" xlink:to="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-7070-81e1-d4f58c86b2ce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-75f0-887f-58988dd497d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_OtherCommitmentsAxis_019e6946-ff8e-7070-81e1-d4f58c86b2ce" xlink:to="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-75f0-887f-58988dd497d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ForwardStartingSecuredFinancingReceivablesMember_019e6946-ff8e-7856-9f09-0aede1c3c19e" xlink:href="ms-20260630.xsd#ms_ForwardStartingSecuredFinancingReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-75f0-887f-58988dd497d7" xlink:to="loc_ms_ForwardStartingSecuredFinancingReceivablesMember_019e6946-ff8e-7856-9f09-0aede1c3c19e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CentralCounterpartyCommitmentMember_019e6946-ff8e-7879-8e89-6224c962a628" xlink:href="ms-20260630.xsd#ms_CentralCounterpartyCommitmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-75f0-887f-58988dd497d7" xlink:to="loc_ms_CentralCounterpartyCommitmentMember_019e6946-ff8e-7879-8e89-6224c962a628" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommitmentsInvestmentActivitiesMember_019e6946-ff8e-7346-b2f1-9a4f0fddd84e" xlink:href="ms-20260630.xsd#ms_CommitmentsInvestmentActivitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-75f0-887f-58988dd497d7" xlink:to="loc_ms_CommitmentsInvestmentActivitiesMember_019e6946-ff8e-7346-b2f1-9a4f0fddd84e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommitmentsLettersOfCreditAndOtherFinancialGuaranteesObtainedToSatisfyCollateralRequirementsMember_019e6946-ff8e-7d9b-9af7-ce6455cf0a2f" xlink:href="ms-20260630.xsd#ms_CommitmentsLettersOfCreditAndOtherFinancialGuaranteesObtainedToSatisfyCollateralRequirementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_019e6946-ff8e-75f0-887f-58988dd497d7" xlink:to="loc_ms_CommitmentsLettersOfCreditAndOtherFinancialGuaranteesObtainedToSatisfyCollateralRequirementsMember_019e6946-ff8e-7d9b-9af7-ce6455cf0a2f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentFiscalYearMaturityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_019e6946-ff8e-76a1-9311-7eb442bd4452" xlink:to="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentDueInNextTwelveMonths_019e6946-ff8e-73b7-b498-5077e481b03c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentDueInNextTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:to="loc_us-gaap_OtherCommitmentDueInNextTwelveMonths_019e6946-ff8e-73b7-b498-5077e481b03c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentDueInSecondAndThirdYear_019e6946-ff8e-7061-af1f-afd0c0629d96" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentDueInSecondAndThirdYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:to="loc_us-gaap_OtherCommitmentDueInSecondAndThirdYear_019e6946-ff8e-7061-af1f-afd0c0629d96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentDueInFourthAndFifthYear_019e6946-ff8e-7dbf-a71f-81da93864a7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentDueInFourthAndFifthYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:to="loc_us-gaap_OtherCommitmentDueInFourthAndFifthYear_019e6946-ff8e-7dbf-a71f-81da93864a7c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentDueAfterFifthYear_019e6946-ff8e-72f7-9f36-2f6880cb0976" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentDueAfterFifthYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:to="loc_us-gaap_OtherCommitmentDueAfterFifthYear_019e6946-ff8e-72f7-9f36-2f6880cb0976" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitment_019e6946-ff8e-7cfc-8767-ec4b684e5833" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentFiscalYearMaturityAbstract_019e6946-ff8e-7c75-9b2e-d0e46a806940" xlink:to="loc_us-gaap_OtherCommitment_019e6946-ff8e-7cfc-8767-ec4b684e5833" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommitmentsParticipatedToThirdParties_019e6946-ff8e-72f8-b37a-0e485e71e053" xlink:href="ms-20260630.xsd#ms_CommitmentsParticipatedToThirdParties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsLineItems_019e6946-ff8e-76a1-9311-7eb442bd4452" xlink:to="loc_ms_CommitmentsParticipatedToThirdParties_019e6946-ff8e-72f8-b37a-0e485e71e053" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/CommitmentsGuaranteesandContingenciesObligationsunderGuaranteeArrangementsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#CommitmentsGuaranteesandContingenciesObligationsunderGuaranteeArrangementsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/CommitmentsGuaranteesandContingenciesObligationsunderGuaranteeArrangementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLineItems_019e6946-ff8e-7348-bb71-f06106ef337e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019e6946-ff8e-73b4-8a09-b584b4655104" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfGuaranteeObligationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019e6946-ff8e-7348-bb71-f06106ef337e" xlink:to="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019e6946-ff8e-73b4-8a09-b584b4655104" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnderlyingAssetClassAxis_019e6946-ff8e-7c89-aa05-5c58f22e7c74" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnderlyingAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019e6946-ff8e-73b4-8a09-b584b4655104" xlink:to="loc_us-gaap_UnderlyingAssetClassAxis_019e6946-ff8e-7c89-aa05-5c58f22e7c74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-7c89-aa05-5c58f22e7c74_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnderlyingAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_UnderlyingAssetClassAxis_019e6946-ff8e-7c89-aa05-5c58f22e7c74" xlink:to="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-7c89-aa05-5c58f22e7c74_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnderlyingAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_UnderlyingAssetClassAxis_019e6946-ff8e-7c89-aa05-5c58f22e7c74" xlink:to="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeMember_019e6946-ff8e-769e-90c3-b85a43183d65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_us-gaap_DerivativeMember_019e6946-ff8e-769e-90c3-b85a43183d65" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StandbyLettersOfCreditMember_019e6946-ff8e-774e-b6af-ada47ba9aaf8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StandbyLettersOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_us-gaap_StandbyLettersOfCreditMember_019e6946-ff8e-774e-b6af-ada47ba9aaf8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LiquidityFacilitiesGuaranteeMember_019e6946-ff8e-76ad-a3e8-19ee0136f2bc" xlink:href="ms-20260630.xsd#ms_LiquidityFacilitiesGuaranteeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_ms_LiquidityFacilitiesGuaranteeMember_019e6946-ff8e-76ad-a3e8-19ee0136f2bc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_WholeLoanSalesRepresentationsAndWarrantiesMember_019e6946-ff8e-7738-a85e-e3d97a7b0f9f" xlink:href="ms-20260630.xsd#ms_WholeLoanSalesRepresentationsAndWarrantiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_ms_WholeLoanSalesRepresentationsAndWarrantiesMember_019e6946-ff8e-7738-a85e-e3d97a7b0f9f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SecuritizationsRepresentationsAndGuaranteesMember_019e6946-ff8e-7e3e-99fa-782515bd6d31" xlink:href="ms-20260630.xsd#ms_SecuritizationsRepresentationsAndGuaranteesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_ms_SecuritizationsRepresentationsAndGuaranteesMember_019e6946-ff8e-7e3e-99fa-782515bd6d31" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_GeneralPartnerGuaranteeMember_019e6946-ff8e-7b6f-9775-848a62207800" xlink:href="ms-20260630.xsd#ms_GeneralPartnerGuaranteeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_ms_GeneralPartnerGuaranteeMember_019e6946-ff8e-7b6f-9775-848a62207800" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ClearingMemberGuaranteeMember_019e6946-ff8e-74fc-be8e-931db80e2024" xlink:href="ms-20260630.xsd#ms_ClearingMemberGuaranteeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnderlyingAssetClassDomain_019e6946-ff8e-75c7-b5fd-f28ce5d78691" xlink:to="loc_ms_ClearingMemberGuaranteeMember_019e6946-ff8e-74fc-be8e-931db80e2024" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-7cd5-95a6-e63f3f3c0991" xlink:href="ms-20260630.xsd#ms_CreditDerivativesByMaturityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019e6946-ff8e-73b4-8a09-b584b4655104" xlink:to="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-7cd5-95a6-e63f3f3c0991" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-7cd5-95a6-e63f3f3c0991_default" xlink:href="ms-20260630.xsd#ms_CreditDerivativesByMaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-7cd5-95a6-e63f3f3c0991" xlink:to="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-7cd5-95a6-e63f3f3c0991_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-752c-9fd3-d6c95090220b" xlink:href="ms-20260630.xsd#ms_CreditDerivativesByMaturityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_CreditDerivativesByMaturityAxis_019e6946-ff8e-7cd5-95a6-e63f3f3c0991" xlink:to="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-752c-9fd3-d6c95090220b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LessThanTwelveMonthsFromBalanceSheetDateMember_019e6946-ff8e-74e6-a32f-a9a201498b9a" xlink:href="ms-20260630.xsd#ms_LessThanTwelveMonthsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-752c-9fd3-d6c95090220b" xlink:to="loc_ms_LessThanTwelveMonthsFromBalanceSheetDateMember_019e6946-ff8e-74e6-a32f-a9a201498b9a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MoreThanOneAndWithinThreeYearsFromBalanceSheetDateMember_019e6946-ff8e-7c2e-8f8b-9fc2a47e553c" xlink:href="ms-20260630.xsd#ms_MoreThanOneAndWithinThreeYearsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-752c-9fd3-d6c95090220b" xlink:to="loc_ms_MoreThanOneAndWithinThreeYearsFromBalanceSheetDateMember_019e6946-ff8e-7c2e-8f8b-9fc2a47e553c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MoreThanThreeAndWithinFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-78c9-9e48-af993842629e" xlink:href="ms-20260630.xsd#ms_MoreThanThreeAndWithinFiveYearsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-752c-9fd3-d6c95090220b" xlink:to="loc_ms_MoreThanThreeAndWithinFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-78c9-9e48-af993842629e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MoreThanFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-73b4-8c91-f0c0423806a7" xlink:href="ms-20260630.xsd#ms_MoreThanFiveYearsFromBalanceSheetDateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_CreditDerivativesByMaturityDomain_019e6946-ff8e-752c-9fd3-d6c95090220b" xlink:to="loc_ms_MoreThanFiveYearsFromBalanceSheetDateMember_019e6946-ff8e-73b4-8c91-f0c0423806a7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_019e6946-ff8e-7755-9163-47f3be360608" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsMaximumExposure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019e6946-ff8e-7348-bb71-f06106ef337e" xlink:to="loc_us-gaap_GuaranteeObligationsMaximumExposure_019e6946-ff8e-7755-9163-47f3be360608" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_GuarantorObligationsAssetsCurrentCarryingValue_019e6946-ff8e-7b18-87f7-53c65ed8f246" xlink:href="ms-20260630.xsd#ms_GuarantorObligationsAssetsCurrentCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019e6946-ff8e-7348-bb71-f06106ef337e" xlink:to="loc_ms_GuarantorObligationsAssetsCurrentCarryingValue_019e6946-ff8e-7b18-87f7-53c65ed8f246" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_019e6946-ff8e-7f67-b19e-6acc8610f161" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019e6946-ff8e-7348-bb71-f06106ef337e" xlink:to="loc_us-gaap_LineOfCredit_019e6946-ff8e-7f67-b19e-6acc8610f161" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_LongTermLineOfCreditAllowanceForCreditLoss_019e6946-ff8e-7407-966f-aac31afd0b4a" xlink:href="ms-20260630.xsd#ms_LongTermLineOfCreditAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019e6946-ff8e-7348-bb71-f06106ef337e" xlink:to="loc_ms_LongTermLineOfCreditAllowanceForCreditLoss_019e6946-ff8e-7407-966f-aac31afd0b4a" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/CommitmentsGuaranteesandContingenciesNarrativeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#CommitmentsGuaranteesandContingenciesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/CommitmentsGuaranteesandContingenciesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_019e6946-ff8e-7323-88da-9b8bece07ece" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_019e6946-ff8e-75d0-a2fa-2a7b3bf3998b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_019e6946-ff8e-7323-88da-9b8bece07ece" xlink:to="loc_us-gaap_LossContingenciesTable_019e6946-ff8e-75d0-a2fa-2a7b3bf3998b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseAxis_019e6946-ff8e-7548-9625-00eb08b3e035" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_LitigationCaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019e6946-ff8e-75d0-a2fa-2a7b3bf3998b" xlink:to="loc_srt_LitigationCaseAxis_019e6946-ff8e-7548-9625-00eb08b3e035" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-7548-9625-00eb08b3e035_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_019e6946-ff8e-7548-9625-00eb08b3e035" xlink:to="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-7548-9625-00eb08b3e035_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-73a9-9f79-49f33c64df09" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_019e6946-ff8e-7548-9625-00eb08b3e035" xlink:to="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-73a9-9f79-49f33c64df09" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_UnitedStatesDistrictCourtForTheSouthernDistrictOfNewYorkSDNYStyledInReInterestRateSwapsAntitrustLitigationMember_019e6946-ff8e-7b08-87b5-1a5a2a166635" xlink:href="ms-20260630.xsd#ms_UnitedStatesDistrictCourtForTheSouthernDistrictOfNewYorkSDNYStyledInReInterestRateSwapsAntitrustLitigationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-73a9-9f79-49f33c64df09" xlink:to="loc_ms_UnitedStatesDistrictCourtForTheSouthernDistrictOfNewYorkSDNYStyledInReInterestRateSwapsAntitrustLitigationMember_019e6946-ff8e-7b08-87b5-1a5a2a166635" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CityOfPhiladelphiaEtAl.V.BankOfAmericaCorporationEtAl.Member_019e6946-ff8e-7e94-9b8e-c5004229c31f" xlink:href="ms-20260630.xsd#ms_CityOfPhiladelphiaEtAl.V.BankOfAmericaCorporationEtAl.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-73a9-9f79-49f33c64df09" xlink:to="loc_ms_CityOfPhiladelphiaEtAl.V.BankOfAmericaCorporationEtAl.Member_019e6946-ff8e-7e94-9b8e-c5004229c31f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_IKBInternationalS.A.InLiquidationEtAl.V.MorganStanleyEtAl.Member_019e6946-ff8e-7812-8461-3fa2102adb72" xlink:href="ms-20260630.xsd#ms_IKBInternationalS.A.InLiquidationEtAl.V.MorganStanleyEtAl.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_019e6946-ff8e-73a9-9f79-49f33c64df09" xlink:to="loc_ms_IKBInternationalS.A.InLiquidationEtAl.V.MorganStanleyEtAl.Member_019e6946-ff8e-7812-8461-3fa2102adb72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusAxis_019e6946-ff8e-7712-8fb7-98f90ac1828d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LitigationStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019e6946-ff8e-75d0-a2fa-2a7b3bf3998b" xlink:to="loc_us-gaap_LitigationStatusAxis_019e6946-ff8e-7712-8fb7-98f90ac1828d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusDomain_019e6946-ff8e-7712-8fb7-98f90ac1828d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LitigationStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LitigationStatusAxis_019e6946-ff8e-7712-8fb7-98f90ac1828d" xlink:to="loc_us-gaap_LitigationStatusDomain_019e6946-ff8e-7712-8fb7-98f90ac1828d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LitigationStatusDomain_019e6946-ff8e-75ab-9d44-9c5d2bb5188a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LitigationStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LitigationStatusAxis_019e6946-ff8e-7712-8fb7-98f90ac1828d" xlink:to="loc_us-gaap_LitigationStatusDomain_019e6946-ff8e-75ab-9d44-9c5d2bb5188a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PendingLitigationMember_019e6946-ff8e-76b1-a7de-d9c466654e39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PendingLitigationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LitigationStatusDomain_019e6946-ff8e-75ab-9d44-9c5d2bb5188a" xlink:to="loc_us-gaap_PendingLitigationMember_019e6946-ff8e-76b1-a7de-d9c466654e39" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NumberOfSwapExecutionFacilities_019e6946-ff8e-7b6c-ba6d-713da5811ad2" xlink:href="ms-20260630.xsd#ms_NumberOfSwapExecutionFacilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019e6946-ff8e-7323-88da-9b8bece07ece" xlink:to="loc_ms_NumberOfSwapExecutionFacilities_019e6946-ff8e-7b6c-ba6d-713da5811ad2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NumberOfAntitrustClassActionComplaints_019e6946-ff8e-7190-8eca-8bde1c5c53ea" xlink:href="ms-20260630.xsd#ms_NumberOfAntitrustClassActionComplaints"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019e6946-ff8e-7323-88da-9b8bece07ece" xlink:to="loc_ms_NumberOfAntitrustClassActionComplaints_019e6946-ff8e-7190-8eca-8bde1c5c53ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CertificatesAllegedlySponsoredUnderwrittenAndOrSold_019e6946-ff8e-7750-a02b-54c44e813fa4" xlink:href="ms-20260630.xsd#ms_CertificatesAllegedlySponsoredUnderwrittenAndOrSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019e6946-ff8e-7323-88da-9b8bece07ece" xlink:to="loc_ms_CertificatesAllegedlySponsoredUnderwrittenAndOrSold_019e6946-ff8e-7750-a02b-54c44e813fa4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NumberOfCertificatesDismissed_019e6946-ff8e-7c21-9e1d-34c71cf97cfe" xlink:href="ms-20260630.xsd#ms_NumberOfCertificatesDismissed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019e6946-ff8e-7323-88da-9b8bece07ece" xlink:to="loc_ms_NumberOfCertificatesDismissed_019e6946-ff8e-7c21-9e1d-34c71cf97cfe" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesAssetsandLiabilitiesbyTypeofActivityDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesAssetsandLiabilitiesbyTypeofActivityDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesAssetsandLiabilitiesbyTypeofActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7784-943b-320aad344033" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7b51-b756-465b053b54df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7784-943b-320aad344033" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7b51-b756-465b053b54df" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-70a8-b0aa-5e551eb0b91d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7b51-b756-465b053b54df" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-70a8-b0aa-5e551eb0b91d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-70a8-b0aa-5e551eb0b91d_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-70a8-b0aa-5e551eb0b91d" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-70a8-b0aa-5e551eb0b91d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7a28-bd0c-bdf77b53d403" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-70a8-b0aa-5e551eb0b91d" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7a28-bd0c-bdf77b53d403" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019e6946-ff8e-7a7a-8e3e-f73e6ebee490" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7a28-bd0c-bdf77b53d403" xlink:to="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019e6946-ff8e-7a7a-8e3e-f73e6ebee490" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-74f5-939e-5d2555b874d9" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityByProductGroupAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7b51-b756-465b053b54df" xlink:to="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-74f5-939e-5d2555b874d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-74f5-939e-5d2555b874d9_default" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityProductGroupDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-74f5-939e-5d2555b874d9" xlink:to="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-74f5-939e-5d2555b874d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7636-be69-b4693bf7a56d" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityProductGroupDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-74f5-939e-5d2555b874d9" xlink:to="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7636-be69-b4693bf7a56d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-ff8e-7c42-ba37-741a230104ba" xlink:href="ms-20260630.xsd#ms_MortgageAndAssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7636-be69-b4693bf7a56d" xlink:to="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-ff8e-7c42-ba37-741a230104ba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentVehiclesMember_019e6946-ff8e-7816-94fd-452b59f06afe" xlink:href="ms-20260630.xsd#ms_InvestmentVehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7636-be69-b4693bf7a56d" xlink:to="loc_ms_InvestmentVehiclesMember_019e6946-ff8e-7816-94fd-452b59f06afe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MunicipalTenderOptionBondsMember_019e6946-ff8e-72aa-a2cb-70bcf8218190" xlink:href="ms-20260630.xsd#ms_MunicipalTenderOptionBondsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7636-be69-b4693bf7a56d" xlink:to="loc_ms_MunicipalTenderOptionBondsMember_019e6946-ff8e-72aa-a2cb-70bcf8218190" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherVariableInterestsMember_019e6946-ff8e-7944-a59a-f8ba0d8ca4bb" xlink:href="ms-20260630.xsd#ms_OtherVariableInterestsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7636-be69-b4693bf7a56d" xlink:to="loc_ms_OtherVariableInterestsMember_019e6946-ff8e-7944-a59a-f8ba0d8ca4bb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e6946-ff8e-7c24-b5d0-d0643aab911f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7784-943b-320aad344033" xlink:to="loc_us-gaap_Assets_019e6946-ff8e-7c24-b5d0-d0643aab911f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e6946-ff8e-70d8-8ff9-84ce4261bbf8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7784-943b-320aad344033" xlink:to="loc_us-gaap_Liabilities_019e6946-ff8e-70d8-8ff9-84ce4261bbf8" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesAssetsandLiabilitiesbyBalanceSheetCaptionDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesAssetsandLiabilitiesbyBalanceSheetCaptionDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesAssetsandLiabilitiesbyBalanceSheetCaptionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7fbe-a096-e7dc279d487b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7f1f-aa91-97e211ad51bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7fbe-a096-e7dc279d487b" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7f1f-aa91-97e211ad51bf" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-7aa2-b0ee-9759a2858121" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7f1f-aa91-97e211ad51bf" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-7aa2-b0ee-9759a2858121" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7aa2-b0ee-9759a2858121_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-7aa2-b0ee-9759a2858121" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7aa2-b0ee-9759a2858121_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7c22-8f49-6c33ad905390" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8e-7aa2-b0ee-9759a2858121" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7c22-8f49-6c33ad905390" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019e6946-ff8e-71dc-b2b5-96daf940ac30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8e-7c22-8f49-6c33ad905390" xlink:to="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019e6946-ff8e-71dc-b2b5-96daf940ac30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7fbe-a096-e7dc279d487b" xlink:to="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e6946-ff8e-7a35-9185-be2f44ff4c73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e6946-ff8e-7a35-9185-be2f44ff4c73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TradingAssetsFairValueDisclosure_019e6946-ff8e-7b76-9fc7-a54ca719baa3" xlink:href="ms-20260630.xsd#ms_TradingAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:to="loc_ms_TradingAssetsFairValueDisclosure_019e6946-ff8e-7b76-9fc7-a54ca719baa3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-ff8e-7113-8e5b-a8ad332b198c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_019e6946-ff8e-7113-8e5b-a8ad332b198c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_019e6946-ff8e-7e96-bbc6-4615fe57f3cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:to="loc_us-gaap_OtherReceivables_019e6946-ff8e-7e96-bbc6-4615fe57f3cd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_019e6946-ff8e-7de0-ba1a-5ac2ec88deec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:to="loc_us-gaap_OtherAssets_019e6946-ff8e-7de0-ba1a-5ac2ec88deec" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e6946-ff8e-7a74-aeb7-c9baa3273674" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e6946-ff8e-7a14-84da-fe7daeb514d5" xlink:to="loc_us-gaap_Assets_019e6946-ff8e-7a74-aeb7-c9baa3273674" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7fbe-a096-e7dc279d487b" xlink:to="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsSoldNotYetPurchasedAtFairValue_019e6946-ff8e-7cb4-85c5-e48f24286816" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsSoldNotYetPurchasedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:to="loc_us-gaap_FinancialInstrumentsSoldNotYetPurchasedAtFairValue_019e6946-ff8e-7cb4-85c5-e48f24286816" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherSecuredFinancings_019e6946-ff8e-70f6-acfb-1b939e6303da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherSecuredFinancings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:to="loc_us-gaap_OtherSecuredFinancings_019e6946-ff8e-70f6-acfb-1b939e6303da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_019e6946-ff8e-7b18-aeb2-6d6f599e9062" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:to="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_019e6946-ff8e-7b18-aeb2-6d6f599e9062" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtLongtermAndShorttermCombinedAmount_019e6946-ff8e-710f-8011-9f658cc68c9a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtLongtermAndShorttermCombinedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:to="loc_us-gaap_DebtLongtermAndShorttermCombinedAmount_019e6946-ff8e-710f-8011-9f658cc68c9a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e6946-ff8e-7639-8622-e400641c486a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019e6946-ff8e-7e41-8a38-a77c835e9bba" xlink:to="loc_us-gaap_Liabilities_019e6946-ff8e-7639-8622-e400641c486a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonredeemableNoncontrollingInterest_019e6946-ff8e-7c69-abb1-fbbec95659ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonredeemableNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8e-7fbe-a096-e7dc279d487b" xlink:to="loc_us-gaap_NonredeemableNoncontrollingInterest_019e6946-ff8e-7c69-abb1-fbbec95659ab" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesNonConsolidatedVIEsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesNonConsolidatedVIEsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesNonConsolidatedVIEsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7eff-ac9c-c9315b5cb96d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7eff-ac9c-c9315b5cb96d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-7861-8a3f-0846a339c244" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityByProductGroupAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7eff-ac9c-c9315b5cb96d" xlink:to="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-7861-8a3f-0846a339c244" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7861-8a3f-0846a339c244_default" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityProductGroupDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-7861-8a3f-0846a339c244" xlink:to="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-7861-8a3f-0846a339c244_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityProductGroupDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8e-7861-8a3f-0846a339c244" xlink:to="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-ff8e-7d91-af62-bcd6fc34dc30" xlink:href="ms-20260630.xsd#ms_MortgageAndAssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:to="loc_ms_MortgageAndAssetBackedSecuritiesMember_019e6946-ff8e-7d91-af62-bcd6fc34dc30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedDebtObligationsMember_019e6946-ff8e-770d-a718-f67ac8bcd991" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedDebtObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:to="loc_us-gaap_CollateralizedDebtObligationsMember_019e6946-ff8e-770d-a718-f67ac8bcd991" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MunicipalTenderOptionBondsMember_019e6946-ff8e-75f8-a20c-3bf07d4098d1" xlink:href="ms-20260630.xsd#ms_MunicipalTenderOptionBondsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:to="loc_ms_MunicipalTenderOptionBondsMember_019e6946-ff8e-75f8-a20c-3bf07d4098d1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StructuredFinanceMember_019e6946-ff8e-7f55-8593-56c75546e004" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StructuredFinanceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:to="loc_us-gaap_StructuredFinanceMember_019e6946-ff8e-7f55-8593-56c75546e004" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherVariableInterestsMember_019e6946-ff8e-7c8a-b755-08a6da506175" xlink:href="ms-20260630.xsd#ms_OtherVariableInterestsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8e-750e-8a4b-3c9a077c3a67" xlink:to="loc_ms_OtherVariableInterestsMember_019e6946-ff8e-7c8a-b755-08a6da506175" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8e-79c5-9fee-9446f2e831c4" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityByInterestAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7eff-ac9c-c9315b5cb96d" xlink:to="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8e-79c5-9fee-9446f2e831c4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8e-79c5-9fee-9446f2e831c4_default" xlink:href="ms-20260630.xsd#ms_InterestInVariableInterestEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8e-79c5-9fee-9446f2e831c4" xlink:to="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8e-79c5-9fee-9446f2e831c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8e-7968-a068-1fbb31cadbed" xlink:href="ms-20260630.xsd#ms_InterestInVariableInterestEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8e-79c5-9fee-9446f2e831c4" xlink:to="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8e-7968-a068-1fbb31cadbed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsMember_019e6946-ff8e-75af-98bf-607b25f80151" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8e-7968-a068-1fbb31cadbed" xlink:to="loc_us-gaap_AssetsMember_019e6946-ff8e-75af-98bf-607b25f80151" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_DebtandEquityInterestsMember_019e6946-ff8f-7426-a41c-1a3bf39d82cf" xlink:href="ms-20260630.xsd#ms_DebtandEquityInterestsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-ff8e-75af-98bf-607b25f80151" xlink:to="loc_ms_DebtandEquityInterestsMember_019e6946-ff8f-7426-a41c-1a3bf39d82cf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFinancialInstrumentsAssetsMember_019e6946-ff8f-796a-9534-f6812efdc358" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFinancialInstrumentsAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-ff8e-75af-98bf-607b25f80151" xlink:to="loc_us-gaap_DerivativeFinancialInstrumentsAssetsMember_019e6946-ff8f-796a-9534-f6812efdc358" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommitmentsGuaranteesAndOtherMember_019e6946-ff8f-7ed2-bf52-30bf2ff9603f" xlink:href="ms-20260630.xsd#ms_CommitmentsGuaranteesAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsMember_019e6946-ff8e-75af-98bf-607b25f80151" xlink:to="loc_ms_CommitmentsGuaranteesAndOtherMember_019e6946-ff8f-7ed2-bf52-30bf2ff9603f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityMember_019e6946-ff8f-7545-9f16-e6d0bcfd9bf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8e-7968-a068-1fbb31cadbed" xlink:to="loc_us-gaap_LiabilityMember_019e6946-ff8f-7545-9f16-e6d0bcfd9bf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember_019e6946-ff8f-73b5-9ad9-3deb8ba42a62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityMember_019e6946-ff8f-7545-9f16-e6d0bcfd9bf0" xlink:to="loc_us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember_019e6946-ff8f-73b5-9ad9-3deb8ba42a62" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-78ef-953d-fd8c79e6058b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8e-7eff-ac9c-c9315b5cb96d" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-78ef-953d-fd8c79e6058b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-78ef-953d-fd8c79e6058b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-78ef-953d-fd8c79e6058b" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-78ef-953d-fd8c79e6058b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-7cd2-9332-793b39cf8b3c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-78ef-953d-fd8c79e6058b" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-7cd2-9332-793b39cf8b3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember_019e6946-ff8f-7843-8c4a-7d19abe14766" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-7cd2-9332-793b39cf8b3c" xlink:to="loc_us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember_019e6946-ff8f-7843-8c4a-7d19abe14766" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityReportingEntityInvolvementUnpaidPrincipalBalanceAmount_019e6946-ff8f-733a-a3d7-6e0f14a9648f" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityReportingEntityInvolvementUnpaidPrincipalBalanceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:to="loc_ms_VariableInterestEntityReportingEntityInvolvementUnpaidPrincipalBalanceAmount_019e6946-ff8f-733a-a3d7-6e0f14a9648f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount_019e6946-ff8f-7734-93c4-961f188a6c30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:to="loc_us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount_019e6946-ff8f-7734-93c4-961f188a6c30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e6946-ff8f-777e-bf49-ee69395216b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:to="loc_us-gaap_Assets_019e6946-ff8f-777e-bf49-ee69395216b2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityAssetsIssuedBySecuritizationSpecialPurposeEntity_019e6946-ff8f-7dc2-b652-da3d9dcdceb2" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityAssetsIssuedBySecuritizationSpecialPurposeEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:to="loc_ms_VariableInterestEntityAssetsIssuedBySecuritizationSpecialPurposeEntity_019e6946-ff8f-7dc2-b652-da3d9dcdceb2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e6946-ff8f-7183-bf04-525bd9597021" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7cca-bab6-9dd05203dd41" xlink:to="loc_us-gaap_Liabilities_019e6946-ff8f-7183-bf04-525bd9597021" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesMortgageandAssetBackedSecuritizationAssetsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesMortgageandAssetBackedSecuritizationAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesMortgageandAssetBackedSecuritizationAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7ea3-b758-61bc74ab4572" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-71d8-bf1e-0c41d00ea146" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7ea3-b758-61bc74ab4572" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-71d8-bf1e-0c41d00ea146" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-711a-9c5b-b76f741452e8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-71d8-bf1e-0c41d00ea146" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-711a-9c5b-b76f741452e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-711a-9c5b-b76f741452e8_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-711a-9c5b-b76f741452e8" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-711a-9c5b-b76f741452e8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-7e0b-ac2d-406529fb5202" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6946-ff8f-711a-9c5b-b76f741452e8" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-7e0b-ac2d-406529fb5202" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember_019e6946-ff8f-7e37-99e1-7d6473b5dd72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019e6946-ff8f-7e0b-ac2d-406529fb5202" xlink:to="loc_us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember_019e6946-ff8f-7e37-99e1-7d6473b5dd72" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8f-7fcf-b29f-cf56252e5080" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityByInterestAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-71d8-bf1e-0c41d00ea146" xlink:to="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8f-7fcf-b29f-cf56252e5080" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8f-7fcf-b29f-cf56252e5080_default" xlink:href="ms-20260630.xsd#ms_InterestInVariableInterestEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8f-7fcf-b29f-cf56252e5080" xlink:to="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8f-7fcf-b29f-cf56252e5080_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8f-7e03-96a3-df9a2cc470d2" xlink:href="ms-20260630.xsd#ms_InterestInVariableInterestEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_VariableInterestEntityByInterestAxis_019e6946-ff8f-7fcf-b29f-cf56252e5080" xlink:to="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8f-7e03-96a3-df9a2cc470d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesAssetsMember_019e6946-ff8f-78f1-8b14-dfcbb1f972e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_InterestInVariableInterestEntityDomain_019e6946-ff8f-7e03-96a3-df9a2cc470d2" xlink:to="loc_us-gaap_SecuritiesAssetsMember_019e6946-ff8f-78f1-8b14-dfcbb1f972e4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8f-7180-951c-521bd88c4a48" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityByProductGroupAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-71d8-bf1e-0c41d00ea146" xlink:to="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8f-7180-951c-521bd88c4a48" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7180-951c-521bd88c4a48_default" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityProductGroupDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8f-7180-951c-521bd88c4a48" xlink:to="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7180-951c-521bd88c4a48_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7a73-ac44-c57188e23dc6" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityProductGroupDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_VariableInterestEntityByProductGroupAxis_019e6946-ff8f-7180-951c-521bd88c4a48" xlink:to="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7a73-ac44-c57188e23dc6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e6946-ff8f-77cb-90cc-28672b8035a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7a73-ac44-c57188e23dc6" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e6946-ff8f-77cb-90cc-28672b8035a8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e6946-ff8f-72d5-a1c6-895f424e2433" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7a73-ac44-c57188e23dc6" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e6946-ff8f-72d5-a1c6-895f424e2433" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8f-78e1-9d80-4028ed8fe5a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7a73-ac44-c57188e23dc6" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8f-78e1-9d80-4028ed8fe5a9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_OtherConsumerAndCommercialLoansMember_019e6946-ff8f-75e6-b678-b62d852a0b74" xlink:href="ms-20260630.xsd#ms_OtherConsumerAndCommercialLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_VariableInterestEntityProductGroupDomain_019e6946-ff8f-7a73-ac44-c57188e23dc6" xlink:to="loc_ms_OtherConsumerAndCommercialLoansMember_019e6946-ff8f-75e6-b678-b62d852a0b74" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_VariableInterestEntityReportingEntityInvolvementUnpaidPrincipalBalanceAmount_019e6946-ff8f-77d9-88cc-45aab08ebcd6" xlink:href="ms-20260630.xsd#ms_VariableInterestEntityReportingEntityInvolvementUnpaidPrincipalBalanceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7ea3-b758-61bc74ab4572" xlink:to="loc_ms_VariableInterestEntityReportingEntityInvolvementUnpaidPrincipalBalanceAmount_019e6946-ff8f-77d9-88cc-45aab08ebcd6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e6946-ff8f-7de3-bcc8-fda24ffa98dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-7ea3-b758-61bc74ab4572" xlink:to="loc_us-gaap_Assets_019e6946-ff8f-7de3-bcc8-fda24ffa98dc" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesTransferredAssetswithContinuingInvolvementDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesTransferredAssetswithContinuingInvolvementDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesTransferredAssetswithContinuingInvolvementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7927-b3c4-2c377b28cc7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7927-b3c4-2c377b28cc7b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7c95-b5e3-9daafbb1cae0" xlink:href="ms-20260630.xsd#ms_QualifyingSpecialPurposeEntityClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7927-b3c4-2c377b28cc7b" xlink:to="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7c95-b5e3-9daafbb1cae0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7c95-b5e3-9daafbb1cae0_default" xlink:href="ms-20260630.xsd#ms_QualifyingSpecialPurposeEntitiesClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7c95-b5e3-9daafbb1cae0" xlink:to="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7c95-b5e3-9daafbb1cae0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7599-833e-4ba93c0132b9" xlink:href="ms-20260630.xsd#ms_QualifyingSpecialPurposeEntitiesClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7c95-b5e3-9daafbb1cae0" xlink:to="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7599-833e-4ba93c0132b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SpecialPurposeEntitiesMember_019e6946-ff8f-7e5d-a871-2e43b1990bda" xlink:href="ms-20260630.xsd#ms_SpecialPurposeEntitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7599-833e-4ba93c0132b9" xlink:to="loc_ms_SpecialPurposeEntitiesMember_019e6946-ff8f-7e5d-a871-2e43b1990bda" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7349-b1e5-b5ac05ed2f7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7927-b3c4-2c377b28cc7b" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7349-b1e5-b5ac05ed2f7f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7349-b1e5-b5ac05ed2f7f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7349-b1e5-b5ac05ed2f7f" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7349-b1e5-b5ac05ed2f7f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7eea-b3cc-5a7f65305b8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7349-b1e5-b5ac05ed2f7f" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7eea-b3cc-5a7f65305b8a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageMember_019e6946-ff8f-7ff1-83aa-1f0f5cd189a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7eea-b3cc-5a7f65305b8a" xlink:to="loc_us-gaap_ResidentialMortgageMember_019e6946-ff8f-7ff1-83aa-1f0f5cd189a6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e6946-ff8f-7ee9-8cc9-c0e4da684541" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7eea-b3cc-5a7f65305b8a" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e6946-ff8f-7ee9-8cc9-c0e4da684541" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8f-7d2d-a26b-55031f0b1247" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7eea-b3cc-5a7f65305b8a" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e6946-ff8f-7d2d-a26b-55031f0b1247" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CreditLinkedNotesAndOtherMember_019e6946-ff8f-7889-bcdc-d5214bc45445" xlink:href="ms-20260630.xsd#ms_CreditLinkedNotesAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7eea-b3cc-5a7f65305b8a" xlink:to="loc_ms_CreditLinkedNotesAndOtherMember_019e6946-ff8f-7889-bcdc-d5214bc45445" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7872-ae91-5f0095b72446" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7927-b3c4-2c377b28cc7b" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7872-ae91-5f0095b72446" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7872-ae91-5f0095b72446_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7872-ae91-5f0095b72446" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7872-ae91-5f0095b72446_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-78c1-9a16-a649479ff746" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7872-ae91-5f0095b72446" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-78c1-9a16-a649479ff746" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8f-77a3-b9a0-e6f6522f0799" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-78c1-9a16-a649479ff746" xlink:to="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8f-77a3-b9a0-e6f6522f0799" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8f-7fa6-845c-23facc1000e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalNoninvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-78c1-9a16-a649479ff746" xlink:to="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8f-7fa6-845c-23facc1000e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding_019e6946-ff8f-794a-9760-7e4b19c0d21c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:to="loc_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding_019e6946-ff8f-794a-9760-7e4b19c0d21c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_RetainedInterest_019e6946-ff8f-75cb-ae47-daf47cb887c9" xlink:href="ms-20260630.xsd#ms_RetainedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:to="loc_ms_RetainedInterest_019e6946-ff8f-75cb-ae47-daf47cb887c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InterestsPurchasedInSecondaryMarketFairValue_019e6946-ff8f-7a51-8784-289c29b7ea32" xlink:href="ms-20260630.xsd#ms_InterestsPurchasedInSecondaryMarketFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:to="loc_ms_InterestsPurchasedInSecondaryMarketFairValue_019e6946-ff8f-7a51-8784-289c29b7ea32" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019e6946-ff8f-7374-be19-f78cad4969ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:to="loc_us-gaap_DerivativeAssets_019e6946-ff8f-7374-be19-f78cad4969ba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019e6946-ff8f-7482-8aba-a90d221f2d38" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-71c4-bfbe-66e7b39e832c" xlink:to="loc_us-gaap_DerivativeLiabilities_019e6946-ff8f-7482-8aba-a90d221f2d38" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesFairValueofTransfersofAssetswithContinuingInvolvementDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesFairValueofTransfersofAssetswithContinuingInvolvementDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesFairValueofTransfersofAssetswithContinuingInvolvementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-78aa-930d-dbd1bc070800" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7004-b1a2-76c7de82d816" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-78aa-930d-dbd1bc070800" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7004-b1a2-76c7de82d816" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7d11-b4ca-ef1339a0ec5d" xlink:href="ms-20260630.xsd#ms_QualifyingSpecialPurposeEntityClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7004-b1a2-76c7de82d816" xlink:to="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7d11-b4ca-ef1339a0ec5d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7d11-b4ca-ef1339a0ec5d_default" xlink:href="ms-20260630.xsd#ms_QualifyingSpecialPurposeEntitiesClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7d11-b4ca-ef1339a0ec5d" xlink:to="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-7d11-b4ca-ef1339a0ec5d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-76f3-ad17-2cea34486aed" xlink:href="ms-20260630.xsd#ms_QualifyingSpecialPurposeEntitiesClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_ms_QualifyingSpecialPurposeEntityClassificationAxis_019e6946-ff8f-7d11-b4ca-ef1339a0ec5d" xlink:to="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-76f3-ad17-2cea34486aed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SpecialPurposeEntitiesMember_019e6946-ff8f-77da-aef2-c4659826ee1a" xlink:href="ms-20260630.xsd#ms_SpecialPurposeEntitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_QualifyingSpecialPurposeEntitiesClassificationDomain_019e6946-ff8f-76f3-ad17-2cea34486aed" xlink:to="loc_ms_SpecialPurposeEntitiesMember_019e6946-ff8f-77da-aef2-c4659826ee1a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-ff8f-7864-b04f-821623b59465" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7004-b1a2-76c7de82d816" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-ff8f-7864-b04f-821623b59465" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-ff8f-7864-b04f-821623b59465_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-ff8f-7864-b04f-821623b59465" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-ff8f-7864-b04f-821623b59465_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-ff8f-7259-b416-bca23891d27f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6946-ff8f-7864-b04f-821623b59465" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-ff8f-7259-b416-bca23891d27f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e6946-ff8f-70eb-baf7-23279d5c85e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-ff8f-7259-b416-bca23891d27f" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e6946-ff8f-70eb-baf7-23279d5c85e9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6946-ff8f-725b-bbbd-76ec7c61dada" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6946-ff8f-7259-b416-bca23891d27f" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6946-ff8f-725b-bbbd-76ec7c61dada" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7707-97c0-9737bba7585a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_019e6946-ff8f-7004-b1a2-76c7de82d816" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7707-97c0-9737bba7585a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7707-97c0-9737bba7585a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7707-97c0-9737bba7585a" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7707-97c0-9737bba7585a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7eb3-a8e2-b15adffe2d7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e6946-ff8f-7707-97c0-9737bba7585a" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7eb3-a8e2-b15adffe2d7d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8f-7fd1-bc7a-239a66891339" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7eb3-a8e2-b15adffe2d7d" xlink:to="loc_us-gaap_InternalInvestmentGradeMember_019e6946-ff8f-7fd1-bc7a-239a66891339" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8f-7f26-9b8e-2af8ba0c3c0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalNoninvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e6946-ff8f-7eb3-a8e2-b15adffe2d7d" xlink:to="loc_us-gaap_InternalNoninvestmentGradeMember_019e6946-ff8f-7f26-9b8e-2af8ba0c3c0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedInterestFairValueDisclosure_019e6946-ff8f-7109-b8bf-6207715d97e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedInterestFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-78aa-930d-dbd1bc070800" xlink:to="loc_us-gaap_RetainedInterestFairValueDisclosure_019e6946-ff8f-7109-b8bf-6207715d97e5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InterestsPurchasedInSecondaryMarketFairValue_019e6946-ff8f-76ea-8344-11ea58d2dca8" xlink:href="ms-20260630.xsd#ms_InterestsPurchasedInSecondaryMarketFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-78aa-930d-dbd1bc070800" xlink:to="loc_ms_InterestsPurchasedInSecondaryMarketFairValue_019e6946-ff8f-76ea-8344-11ea58d2dca8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019e6946-ff8f-7380-9df3-f7b8abbf0a8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-78aa-930d-dbd1bc070800" xlink:to="loc_us-gaap_DerivativeAssets_019e6946-ff8f-7380-9df3-f7b8abbf0a8c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019e6946-ff8f-7587-815b-8c99859d7786" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_019e6946-ff8f-78aa-930d-dbd1bc070800" xlink:to="loc_us-gaap_DerivativeLiabilities_019e6946-ff8f-7587-815b-8c99859d7786" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesAssetsSoldwithRetainedExposureDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#VariableInterestEntitiesandSecuritizationActivitiesAssetsSoldwithRetainedExposureDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/VariableInterestEntitiesandSecuritizationActivitiesAssetsSoldwithRetainedExposureDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesLineItems_019e6946-ff8f-7400-813c-96e4bd9772a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransferOfFinancialAssetsAccountedForAsSalesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTable_019e6946-ff8f-7436-8a84-b36ae5ef6be2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesLineItems_019e6946-ff8f-7400-813c-96e4bd9772a7" xlink:to="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTable_019e6946-ff8f-7436-8a84-b36ae5ef6be2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7d6d-9de5-959045ee1033" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTable_019e6946-ff8f-7436-8a84-b36ae5ef6be2" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7d6d-9de5-959045ee1033" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7d6d-9de5-959045ee1033_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7d6d-9de5-959045ee1033" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7d6d-9de5-959045ee1033_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7447-b48e-de8f3eac0dcf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e6946-ff8f-7d6d-9de5-959045ee1033" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7447-b48e-de8f3eac0dcf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityContractMember_019e6946-ff8f-78e6-ac8c-25d1cac482f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e6946-ff8f-7447-b48e-de8f3eac0dcf" xlink:to="loc_us-gaap_EquityContractMember_019e6946-ff8f-78e6-ac8c-25d1cac482f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodAxis_019eff31-2562-7dc0-9543-0756f087e446" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesTable_019e6946-ff8f-7436-8a84-b36ae5ef6be2" xlink:to="loc_us-gaap_TransactionMarketMethodAxis_019eff31-2562-7dc0-9543-0756f087e446" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodDomain_019eff31-2562-7dc0-9543-0756f087e446_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TransactionMarketMethodAxis_019eff31-2562-7dc0-9543-0756f087e446" xlink:to="loc_us-gaap_TransactionMarketMethodDomain_019eff31-2562-7dc0-9543-0756f087e446_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionMarketMethodDomain_019eff31-2562-7bca-b093-82feeb9e1b40" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionMarketMethodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TransactionMarketMethodAxis_019eff31-2562-7dc0-9543-0756f087e446" xlink:to="loc_us-gaap_TransactionMarketMethodDomain_019eff31-2562-7bca-b093-82feeb9e1b40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OverTheCounterMember_019e6946-ff8f-78f5-9ed1-bf1a8740dea4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OverTheCounterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionMarketMethodDomain_019eff31-2562-7bca-b093-82feeb9e1b40" xlink:to="loc_us-gaap_OverTheCounterMember_019e6946-ff8f-78f5-9ed1-bf1a8740dea4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesAmountDerecognized_019e6946-ff8f-7f93-8141-546068b939b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransferOfFinancialAssetsAccountedForAsSalesAmountDerecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesLineItems_019e6946-ff8f-7400-813c-96e4bd9772a7" xlink:to="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesAmountDerecognized_019e6946-ff8f-7f93-8141-546068b939b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TransferOfFinancialAssetsAssetsSoldWithRetainedExposureAbstract_019e6946-ff8f-7938-80a5-292385f33679" xlink:href="ms-20260630.xsd#ms_TransferOfFinancialAssetsAssetsSoldWithRetainedExposureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesLineItems_019e6946-ff8f-7400-813c-96e4bd9772a7" xlink:to="loc_ms_TransferOfFinancialAssetsAssetsSoldWithRetainedExposureAbstract_019e6946-ff8f-7938-80a5-292385f33679" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesFairValueOfDerecognizedAssets_019e6946-ff8f-7a1c-a69b-bce4604309f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransferOfFinancialAssetsAccountedForAsSalesFairValueOfDerecognizedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_TransferOfFinancialAssetsAssetsSoldWithRetainedExposureAbstract_019e6946-ff8f-7938-80a5-292385f33679" xlink:to="loc_us-gaap_TransferOfFinancialAssetsAccountedForAsSalesFairValueOfDerecognizedAssets_019e6946-ff8f-7a1c-a69b-bce4604309f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_019e6946-ff8f-7c80-8721-a16a7740b7b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_TransferOfFinancialAssetsAssetsSoldWithRetainedExposureAbstract_019e6946-ff8f-7938-80a5-292385f33679" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_019e6946-ff8f-7c80-8721-a16a7740b7b6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_019e6946-ff8f-7989-ba33-3716d5f09f22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_TransferOfFinancialAssetsAssetsSoldWithRetainedExposureAbstract_019e6946-ff8f-7938-80a5-292385f33679" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_019e6946-ff8f-7989-ba33-3716d5f09f22" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/RegulatoryRequirementsCapitalBufferRequirementsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#RegulatoryRequirementsCapitalBufferRequirementsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/RegulatoryRequirementsCapitalBufferRequirementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7872-b70b-416a77e517bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7872-b70b-416a77e517bd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e6947-0063-7006-920d-8dd00857b491" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7872-b70b-416a77e517bd" xlink:to="loc_srt_RangeAxis_019e6947-0063-7006-920d-8dd00857b491" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6947-0063-7006-920d-8dd00857b491_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e6947-0063-7006-920d-8dd00857b491" xlink:to="loc_srt_RangeMember_019e6947-0063-7006-920d-8dd00857b491_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6947-0063-7d2b-aa15-1d071207609a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e6947-0063-7006-920d-8dd00857b491" xlink:to="loc_srt_RangeMember_019e6947-0063-7d2b-aa15-1d071207609a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e6947-0063-76bb-a47e-2d16e661af68" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6947-0063-7d2b-aa15-1d071207609a" xlink:to="loc_srt_MaximumMember_019e6947-0063-76bb-a47e-2d16e661af68" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationCapitalConservationBufferAbstract_019e6947-0063-75ed-b464-898bbe853fa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BankingRegulationCapitalConservationBufferAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:to="loc_us-gaap_BankingRegulationCapitalConservationBufferAbstract_019e6947-0063-75ed-b464-898bbe853fa3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationCapitalConservationBufferCapitalConservedMinimumAdvanced_019e6947-0063-7cba-9d1c-f84cad58c643" xlink:href="ms-20260630.xsd#ms_BankingRegulationCapitalConservationBufferCapitalConservedMinimumAdvanced"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BankingRegulationCapitalConservationBufferAbstract_019e6947-0063-75ed-b464-898bbe853fa3" xlink:to="loc_ms_BankingRegulationCapitalConservationBufferCapitalConservedMinimumAdvanced_019e6947-0063-7cba-9d1c-f84cad58c643" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationStressCapitalBufferAbstract_019e6947-0063-73bd-9b3f-c884e438efd3" xlink:href="ms-20260630.xsd#ms_BankingRegulationStressCapitalBufferAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:to="loc_ms_BankingRegulationStressCapitalBufferAbstract_019e6947-0063-73bd-9b3f-c884e438efd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationStressCapitalBufferStandardized_019e6947-0063-71c2-befe-d98613537324" xlink:href="ms-20260630.xsd#ms_BankingRegulationStressCapitalBufferStandardized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BankingRegulationStressCapitalBufferAbstract_019e6947-0063-73bd-9b3f-c884e438efd3" xlink:to="loc_ms_BankingRegulationStressCapitalBufferStandardized_019e6947-0063-71c2-befe-d98613537324" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurchargeAbstract_019e6947-0063-704f-bc15-d8fbc5e47f29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurchargeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:to="loc_us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurchargeAbstract_019e6947-0063-704f-bc15-d8fbc5e47f29" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurcharge_019e6947-0063-7432-a707-b7ddf70e20cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurcharge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurchargeAbstract_019e6947-0063-704f-bc15-d8fbc5e47f29" xlink:to="loc_us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurcharge_019e6947-0063-7432-a707-b7ddf70e20cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationGlobalSystemicallyImportantBankGSIBSurchargeAdvanced_019e6947-0063-792c-a87b-7008e2fb2841" xlink:href="ms-20260630.xsd#ms_BankingRegulationGlobalSystemicallyImportantBankGSIBSurchargeAdvanced"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BankingRegulationGlobalSystemicallyImportantBankGsibSurchargeAbstract_019e6947-0063-704f-bc15-d8fbc5e47f29" xlink:to="loc_ms_BankingRegulationGlobalSystemicallyImportantBankGSIBSurchargeAdvanced_019e6947-0063-792c-a87b-7008e2fb2841" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationCountercyclicalCapitalBufferAbstract_019e6947-0063-7d77-bf5d-c6fa06b60e54" xlink:href="ms-20260630.xsd#ms_BankingRegulationCountercyclicalCapitalBufferAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:to="loc_ms_BankingRegulationCountercyclicalCapitalBufferAbstract_019e6947-0063-7d77-bf5d-c6fa06b60e54" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationCountercyclicalCapitalBuffer_019e6947-0063-7ccf-8ccb-5a7ced242b68" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BankingRegulationCountercyclicalCapitalBuffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BankingRegulationCountercyclicalCapitalBufferAbstract_019e6947-0063-7d77-bf5d-c6fa06b60e54" xlink:to="loc_us-gaap_BankingRegulationCountercyclicalCapitalBuffer_019e6947-0063-7ccf-8ccb-5a7ced242b68" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationCountercyclicalCapitalBufferAdvanced_019e6947-0063-7304-b449-1eec80b0b50d" xlink:href="ms-20260630.xsd#ms_BankingRegulationCountercyclicalCapitalBufferAdvanced"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BankingRegulationCountercyclicalCapitalBufferAbstract_019e6947-0063-7d77-bf5d-c6fa06b60e54" xlink:to="loc_ms_BankingRegulationCountercyclicalCapitalBufferAdvanced_019e6947-0063-7304-b449-1eec80b0b50d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationCapitalBufferRequirementAbstract_019e6947-0063-77fe-a53a-178abe5083e2" xlink:href="ms-20260630.xsd#ms_BankingRegulationCapitalBufferRequirementAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-79e3-8235-7824e3897ba6" xlink:to="loc_ms_BankingRegulationCapitalBufferRequirementAbstract_019e6947-0063-77fe-a53a-178abe5083e2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationCapitalBufferRequirement_019e6947-0063-7552-ae27-a1e922a447ac" xlink:href="ms-20260630.xsd#ms_BankingRegulationCapitalBufferRequirement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BankingRegulationCapitalBufferRequirementAbstract_019e6947-0063-77fe-a53a-178abe5083e2" xlink:to="loc_ms_BankingRegulationCapitalBufferRequirement_019e6947-0063-7552-ae27-a1e922a447ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_BankingRegulationCapitalBufferRequirementAdvanced_019e6947-0063-7eef-97f8-9b1fe070654d" xlink:href="ms-20260630.xsd#ms_BankingRegulationCapitalBufferRequirementAdvanced"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_BankingRegulationCapitalBufferRequirementAbstract_019e6947-0063-77fe-a53a-178abe5083e2" xlink:to="loc_ms_BankingRegulationCapitalBufferRequirementAdvanced_019e6947-0063-7eef-97f8-9b1fe070654d" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/RegulatoryRequirementsNarrativeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#RegulatoryRequirementsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/RegulatoryRequirementsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7222-897d-ecf5924f525c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7563-ada1-40adef0d1a3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7222-897d-ecf5924f525c" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7563-ada1-40adef0d1a3b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e6947-0063-7cb8-ad35-6a7edd0d368b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-7563-ada1-40adef0d1a3b" xlink:to="loc_srt_RangeAxis_019e6947-0063-7cb8-ad35-6a7edd0d368b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6947-0063-7cb8-ad35-6a7edd0d368b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e6947-0063-7cb8-ad35-6a7edd0d368b" xlink:to="loc_srt_RangeMember_019e6947-0063-7cb8-ad35-6a7edd0d368b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6947-0063-7ad2-942a-dcb862c52a86" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e6947-0063-7cb8-ad35-6a7edd0d368b" xlink:to="loc_srt_RangeMember_019e6947-0063-7ad2-942a-dcb862c52a86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e6947-0063-7582-b506-dc39ac7097a2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6947-0063-7ad2-942a-dcb862c52a86" xlink:to="loc_srt_MaximumMember_019e6947-0063-7582-b506-dc39ac7097a2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationCountercyclicalCapitalBuffer_019e6947-0063-78f3-9ef7-45b0abfbe030" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BankingRegulationCountercyclicalCapitalBuffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7222-897d-ecf5924f525c" xlink:to="loc_us-gaap_BankingRegulationCountercyclicalCapitalBuffer_019e6947-0063-78f3-9ef7-45b0abfbe030" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/RegulatoryRequirementsUSBankSubsidiariesRegulatoryCapitalandCapitalRatiosDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#RegulatoryRequirementsUSBankSubsidiariesRegulatoryCapitalandCapitalRatiosDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/RegulatoryRequirementsUSBankSubsidiariesRegulatoryCapitalandCapitalRatiosDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7c7a-9e13-510b52931272" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-745f-81f9-782a15d39b7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7c7a-9e13-510b52931272" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-745f-81f9-782a15d39b7f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019e6947-0063-76d7-96a9-ac680894384d" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-745f-81f9-782a15d39b7f" xlink:to="loc_dei_LegalEntityAxis_019e6947-0063-76d7-96a9-ac680894384d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019e6947-0063-76d7-96a9-ac680894384d_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019e6947-0063-76d7-96a9-ac680894384d" xlink:to="loc_dei_EntityDomain_019e6947-0063-76d7-96a9-ac680894384d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019e6947-0063-7f0f-8d9c-7a882c51d052" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019e6947-0063-76d7-96a9-ac680894384d" xlink:to="loc_dei_EntityDomain_019e6947-0063-7f0f-8d9c-7a882c51d052" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MorganStanleyBankNationalAssociationMember_019e6947-0063-788a-aaa4-d631aa028169" xlink:href="ms-20260630.xsd#ms_MorganStanleyBankNationalAssociationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019e6947-0063-7f0f-8d9c-7a882c51d052" xlink:to="loc_ms_MorganStanleyBankNationalAssociationMember_019e6947-0063-788a-aaa4-d631aa028169" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MorganStanleyPrivateBankNationalAssociationMember_019e6947-0063-7572-ac00-832b43994da5" xlink:href="ms-20260630.xsd#ms_MorganStanleyPrivateBankNationalAssociationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019e6947-0063-7f0f-8d9c-7a882c51d052" xlink:to="loc_ms_MorganStanleyPrivateBankNationalAssociationMember_019e6947-0063-7572-ac00-832b43994da5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_WellCapitalizedRequirementRatioAbstract_019e6947-0063-7439-81df-412c2b27beca" xlink:href="ms-20260630.xsd#ms_WellCapitalizedRequirementRatioAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7c7a-9e13-510b52931272" xlink:to="loc_ms_WellCapitalizedRequirementRatioAbstract_019e6947-0063-7439-81df-412c2b27beca" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TierOneRiskBasedCommonCapitalWellCapitalizedRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-7b3f-b476-29f4663e2e3d" xlink:href="ms-20260630.xsd#ms_TierOneRiskBasedCommonCapitalWellCapitalizedRequiredForCapitalAdequacyToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_WellCapitalizedRequirementRatioAbstract_019e6947-0063-7439-81df-412c2b27beca" xlink:to="loc_ms_TierOneRiskBasedCommonCapitalWellCapitalizedRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-7b3f-b476-29f4663e2e3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TierOneRiskBasedWellCapitalizedRequiredforCapitalAdequacytoRiskWeightedAssets_019e6947-0063-75ac-b828-26e14a7715ca" xlink:href="ms-20260630.xsd#ms_TierOneRiskBasedWellCapitalizedRequiredforCapitalAdequacytoRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_WellCapitalizedRequirementRatioAbstract_019e6947-0063-7439-81df-412c2b27beca" xlink:to="loc_ms_TierOneRiskBasedWellCapitalizedRequiredforCapitalAdequacytoRiskWeightedAssets_019e6947-0063-75ac-b828-26e14a7715ca" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_019e6947-0063-7e4b-b493-b5fda2a3b9c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_WellCapitalizedRequirementRatioAbstract_019e6947-0063-7439-81df-412c2b27beca" xlink:to="loc_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_019e6947-0063-7e4b-b493-b5fda2a3b9c6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets_019e6947-0063-7e9a-9850-458d96f3d87b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_WellCapitalizedRequirementRatioAbstract_019e6947-0063-7439-81df-412c2b27beca" xlink:to="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets_019e6947-0063-7e9a-9850-458d96f3d87b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:href="ms-20260630.xsd#ms_MinimumRegulatoryCapitalRatioAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7c7a-9e13-510b52931272" xlink:to="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_TierOneRiskBasedCommonCapitalRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-798c-9393-2471d36972bd" xlink:href="ms-20260630.xsd#ms_TierOneRiskBasedCommonCapitalRequiredForCapitalAdequacyToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:to="loc_ms_TierOneRiskBasedCommonCapitalRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-798c-9393-2471d36972bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-7746-9b8e-0eb928a9571e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-7746-9b8e-0eb928a9571e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-77e2-adbc-931aa39d32d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:to="loc_us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets_019e6947-0063-77e2-adbc-931aa39d32d2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets_019e6947-0063-7e13-b598-f624918fbea8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:to="loc_us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets_019e6947-0063-7e13-b598-f624918fbea8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MinimumSupplementaryLeverageRatio_019e6947-0063-71f7-9574-57d45b537fb9" xlink:href="ms-20260630.xsd#ms_MinimumSupplementaryLeverageRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_MinimumRegulatoryCapitalRatioAbstract_019e6947-0063-77cd-9361-6ba227306f44" xlink:to="loc_ms_MinimumSupplementaryLeverageRatio_019e6947-0063-71f7-9574-57d45b537fb9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:href="ms-20260630.xsd#ms_RegulatoryCapitalRequirementsAmountAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7c7a-9e13-510b52931272" xlink:to="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapital_019e6947-0063-705b-b745-ecaae09b5eee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonEquityTierOneCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:to="loc_us-gaap_CommonEquityTierOneCapital_019e6947-0063-705b-b745-ecaae09b5eee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapital_019e6947-0063-7c9a-aabf-59270916c616" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneRiskBasedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:to="loc_us-gaap_TierOneRiskBasedCapital_019e6947-0063-7c9a-aabf-59270916c616" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Capital_019e6947-0063-7bff-bbab-6a454814f379" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Capital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:to="loc_us-gaap_Capital_019e6947-0063-7bff-bbab-6a454814f379" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapital_019e6947-0063-7ba2-95ef-bb502285aa93" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneLeverageCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:to="loc_us-gaap_TierOneLeverageCapital_019e6947-0063-7ba2-95ef-bb502285aa93" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SupplementalLeverageCapital_019e6947-0063-7dcd-b8f2-7ca236966647" xlink:href="ms-20260630.xsd#ms_SupplementalLeverageCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_RegulatoryCapitalRequirementsAmountAbstract_019e6947-0063-73e0-b0f4-44faffb915f8" xlink:to="loc_ms_SupplementalLeverageCapital_019e6947-0063-7dcd-b8f2-7ca236966647" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RiskBasedRatiosAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7c7a-9e13-510b52931272" xlink:to="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalRatio_019e6947-0063-7b9a-a497-117d220449c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonEquityTierOneCapitalRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:to="loc_us-gaap_CommonEquityTierOneCapitalRatio_019e6947-0063-7b9a-a497-117d220449c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_019e6947-0063-794e-a716-b9fd030ec453" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:to="loc_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_019e6947-0063-794e-a716-b9fd030ec453" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalToRiskWeightedAssets_019e6947-0063-75cc-b8d9-302611a3e00a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalToRiskWeightedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:to="loc_us-gaap_CapitalToRiskWeightedAssets_019e6947-0063-75cc-b8d9-302611a3e00a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalToAverageAssets_019e6947-0063-755b-ba73-989bdf960946" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TierOneLeverageCapitalToAverageAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:to="loc_us-gaap_TierOneLeverageCapitalToAverageAssets_019e6947-0063-755b-ba73-989bdf960946" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementaryLeverageRatio_019e6947-0063-7cec-9b7d-830400b43b4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementaryLeverageRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RiskBasedRatiosAbstract_019e6947-0063-711e-abb0-be26799b0e04" xlink:to="loc_us-gaap_SupplementaryLeverageRatio_019e6947-0063-7cec-9b7d-830400b43b4c" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/RegulatoryRequirementsUSBrokerDealerRegulatoryCapitalRequirementsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#RegulatoryRequirementsUSBrokerDealerRegulatoryCapitalRequirementsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/RegulatoryRequirementsUSBrokerDealerRegulatoryCapitalRequirementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7a46-bc67-68cb2ffb167e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-79ec-916b-d72de930cc61" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7a46-bc67-68cb2ffb167e" xlink:to="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-79ec-916b-d72de930cc61" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019e6947-0063-7845-a58c-ccac363587fb" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_019e6947-0063-79ec-916b-d72de930cc61" xlink:to="loc_dei_LegalEntityAxis_019e6947-0063-7845-a58c-ccac363587fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019e6947-0063-7845-a58c-ccac363587fb_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019e6947-0063-7845-a58c-ccac363587fb" xlink:to="loc_dei_EntityDomain_019e6947-0063-7845-a58c-ccac363587fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019e6947-0063-7831-8208-175cf841ec83" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019e6947-0063-7845-a58c-ccac363587fb" xlink:to="loc_dei_EntityDomain_019e6947-0063-7831-8208-175cf841ec83" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_MSAndCoMember_019e6947-0063-7526-a05b-8bd6e7340e99" xlink:href="ms-20260630.xsd#ms_MSAndCoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019e6947-0063-7831-8208-175cf841ec83" xlink:to="loc_ms_MSAndCoMember_019e6947-0063-7526-a05b-8bd6e7340e99" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NetCapital_019e6947-0063-7669-95b9-eb8aa54b86d8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NetCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7a46-bc67-68cb2ffb167e" xlink:to="loc_srt_NetCapital_019e6947-0063-7669-95b9-eb8aa54b86d8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NetCapitalExcessShortageUnderSecuritiesAndExchangeCommissionRegulationAndCommodityExchangeAct_019e6947-0063-7abe-ae5c-847dc432737d" xlink:href="ms-20260630.xsd#ms_NetCapitalExcessShortageUnderSecuritiesAndExchangeCommissionRegulationAndCommodityExchangeAct"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_019e6947-0063-7a46-bc67-68cb2ffb167e" xlink:to="loc_ms_NetCapitalExcessShortageUnderSecuritiesAndExchangeCommissionRegulationAndCommodityExchangeAct_019e6947-0063-7abe-ae5c-847dc432737d" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/TotalEquityPreferredStockOutstandingDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#TotalEquityPreferredStockOutstandingDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/TotalEquityPreferredStockOutstandingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7346-8896-bda5adc09a51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019e6947-0063-7fe0-b63a-1598545c79e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7346-8896-bda5adc09a51" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019e6947-0063-7fe0-b63a-1598545c79e3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7cbf-a82c-cf0cce0915ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019e6947-0063-7fe0-b63a-1598545c79e3" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7cbf-a82c-cf0cce0915ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7cbf-a82c-cf0cce0915ac_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7cbf-a82c-cf0cce0915ac" xlink:to="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7cbf-a82c-cf0cce0915ac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7cbf-a82c-cf0cce0915ac" xlink:to="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_019e6947-0063-7fff-805c-b94b3c4469ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesAPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_019e6947-0063-7fff-805c-b94b3c4469ba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesCPreferredStockMember_019e6947-0063-7f5e-aee3-14408a06537f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesCPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_us-gaap_SeriesCPreferredStockMember_019e6947-0063-7f5e-aee3-14408a06537f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesEPreferredStockMember_019e6947-0063-7cba-addf-b8af0f1a3b38" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesEPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_us-gaap_SeriesEPreferredStockMember_019e6947-0063-7cba-addf-b8af0f1a3b38" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesFPreferredStockMember_019e6947-0063-7867-8087-1e55fcc2e5e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesFPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_us-gaap_SeriesFPreferredStockMember_019e6947-0063-7867-8087-1e55fcc2e5e2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesIPreferredStockMember_019e6947-0063-7274-89fa-cdb4368acf92" xlink:href="ms-20260630.xsd#ms_SeriesIPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesIPreferredStockMember_019e6947-0063-7274-89fa-cdb4368acf92" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesKPreferredStockMember_019e6947-0063-7496-9641-5bd1ae13abdc" xlink:href="ms-20260630.xsd#ms_SeriesKPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesKPreferredStockMember_019e6947-0063-7496-9641-5bd1ae13abdc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesLPreferredStockMember_019e6947-0063-75a7-a7a7-e386b563e223" xlink:href="ms-20260630.xsd#ms_SeriesLPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesLPreferredStockMember_019e6947-0063-75a7-a7a7-e386b563e223" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesMPreferredStockMember_019e6947-0063-7209-94e6-b5ecdd210b8b" xlink:href="ms-20260630.xsd#ms_SeriesMPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesMPreferredStockMember_019e6947-0063-7209-94e6-b5ecdd210b8b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesNPreferredStockMember_019e6947-0063-73e2-9895-1461a6403d24" xlink:href="ms-20260630.xsd#ms_SeriesNPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesNPreferredStockMember_019e6947-0063-73e2-9895-1461a6403d24" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesOPreferredStockMember_019e6947-0063-77b4-b964-da8fc671d546" xlink:href="ms-20260630.xsd#ms_SeriesOPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesOPreferredStockMember_019e6947-0063-77b4-b964-da8fc671d546" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesPPreferredStockMember_019e6947-0063-7a92-a0c4-d893bc024cf2" xlink:href="ms-20260630.xsd#ms_SeriesPPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesPPreferredStockMember_019e6947-0063-7a92-a0c4-d893bc024cf2" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesQPreferredStockMember_019e6947-0063-7da7-99ac-247e9087055c" xlink:href="ms-20260630.xsd#ms_SeriesQPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7544-8eba-218fa85ed7b6" xlink:to="loc_ms_SeriesQPreferredStockMember_019e6947-0063-7da7-99ac-247e9087055c" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_019e6947-0063-710b-a348-80ad7d28a22a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7346-8896-bda5adc09a51" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_019e6947-0063-710b-a348-80ad7d28a22a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockLiquidationPreference_019e6947-0063-7159-9605-edf84d14ebe1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockLiquidationPreference"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7346-8896-bda5adc09a51" xlink:to="loc_us-gaap_PreferredStockLiquidationPreference_019e6947-0063-7159-9605-edf84d14ebe1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_PreferredStockCarryingValue_019e6947-0063-7648-a399-10b72923d5c8" xlink:href="ms-20260630.xsd#ms_PreferredStockCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7346-8896-bda5adc09a51" xlink:to="loc_ms_PreferredStockCarryingValue_019e6947-0063-7648-a399-10b72923d5c8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_019e6947-0063-7458-8ec3-3d5341c99b5a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7346-8896-bda5adc09a51" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_019e6947-0063-7458-8ec3-3d5341c99b5a" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/TotalEquityDividendsDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#TotalEquityDividendsDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/TotalEquityDividendsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7755-bcb8-e2a73387d87d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019e6947-0063-7d02-916c-cbb69a487b2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7755-bcb8-e2a73387d87d" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019e6947-0063-7d02-916c-cbb69a487b2c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7ee3-bc60-6f63d36ec305" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019e6947-0063-7d02-916c-cbb69a487b2c" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7ee3-bc60-6f63d36ec305" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7ee3-bc60-6f63d36ec305_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7ee3-bc60-6f63d36ec305" xlink:to="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7ee3-bc60-6f63d36ec305_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e6947-0063-7ee3-bc60-6f63d36ec305" xlink:to="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_019e6947-0063-7a2b-95cf-151bb895e782" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesAPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_019e6947-0063-7a2b-95cf-151bb895e782" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesCPreferredStockMember_019e6947-0063-7c78-b757-9640e444c501" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesCPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_us-gaap_SeriesCPreferredStockMember_019e6947-0063-7c78-b757-9640e444c501" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesEPreferredStockMember_019e6947-0063-7e65-9856-96cf1cc291a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesEPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_us-gaap_SeriesEPreferredStockMember_019e6947-0063-7e65-9856-96cf1cc291a9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeriesFPreferredStockMember_019e6947-0063-71ee-8170-0c819483ae73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesFPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_us-gaap_SeriesFPreferredStockMember_019e6947-0063-71ee-8170-0c819483ae73" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesIPreferredStockMember_019e6947-0063-7b20-b0e8-bee2071a83c2" xlink:href="ms-20260630.xsd#ms_SeriesIPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesIPreferredStockMember_019e6947-0063-7b20-b0e8-bee2071a83c2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesKPreferredStockMember_019e6947-0063-7acb-ac65-2a5fa2407c55" xlink:href="ms-20260630.xsd#ms_SeriesKPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesKPreferredStockMember_019e6947-0063-7acb-ac65-2a5fa2407c55" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesLPreferredStockMember_019e6947-0063-7299-b316-37f8e862448b" xlink:href="ms-20260630.xsd#ms_SeriesLPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesLPreferredStockMember_019e6947-0063-7299-b316-37f8e862448b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesMPreferredStockMember_019f90df-7ea6-7131-82cf-d6e9f378acdd" xlink:href="ms-20260630.xsd#ms_SeriesMPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesMPreferredStockMember_019f90df-7ea6-7131-82cf-d6e9f378acdd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesNPreferredStockMember_019e6947-0063-7aca-991b-eae54751133e" xlink:href="ms-20260630.xsd#ms_SeriesNPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesNPreferredStockMember_019e6947-0063-7aca-991b-eae54751133e" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesOPreferredStockMember_019e6947-0063-7df3-acef-677e70a3e663" xlink:href="ms-20260630.xsd#ms_SeriesOPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesOPreferredStockMember_019e6947-0063-7df3-acef-677e70a3e663" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesPPreferredStockMember_019e6947-0063-73c5-af83-1db99a001681" xlink:href="ms-20260630.xsd#ms_SeriesPPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesPPreferredStockMember_019e6947-0063-73c5-af83-1db99a001681" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_SeriesQPreferredStockMember_019e6947-0063-7b9a-828c-998bbc8822a2" xlink:href="ms-20260630.xsd#ms_SeriesQPreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e6947-0063-7d60-bb68-575e3075118c" xlink:to="loc_ms_SeriesQPreferredStockMember_019e6947-0063-7b9a-828c-998bbc8822a2" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPreferredStockAbstract_019e6947-0063-7423-bab2-6c3704bd9bae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsPreferredStockAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7755-bcb8-e2a73387d87d" xlink:to="loc_us-gaap_DividendsPreferredStockAbstract_019e6947-0063-7423-bab2-6c3704bd9bae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockDividendsPerShareDeclared_019e6947-0063-70a6-8421-d3add0bea611" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsPreferredStockAbstract_019e6947-0063-7423-bab2-6c3704bd9bae" xlink:to="loc_us-gaap_PreferredStockDividendsPerShareDeclared_019e6947-0063-70a6-8421-d3add0bea611" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPreferredStock_019e6947-0063-7be0-84f0-f79ba62d6c49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsPreferredStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsPreferredStockAbstract_019e6947-0063-7423-bab2-6c3704bd9bae" xlink:to="loc_us-gaap_DividendsPreferredStock_019e6947-0063-7be0-84f0-f79ba62d6c49" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_019e6947-0063-73bc-8580-7c3931333d4a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7755-bcb8-e2a73387d87d" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_019e6947-0063-73bc-8580-7c3931333d4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_019e6947-0063-7696-8067-a89598b078fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e6947-0063-7755-bcb8-e2a73387d87d" xlink:to="loc_us-gaap_DividendsCommonStock_019e6947-0063-7696-8067-a89598b078fa" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/TotalEquityAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#TotalEquityAccumulatedOtherComprehensiveIncomeLossDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/TotalEquityAccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019e6947-0063-7259-b917-8b9bb88ecbbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019e6947-0063-717d-abca-8535ca83e692" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019e6947-0063-7259-b917-8b9bb88ecbbc" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019e6947-0063-717d-abca-8535ca83e692" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e6947-0063-7975-9ead-3002cdd18bac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019e6947-0063-717d-abca-8535ca83e692" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e6947-0063-7975-9ead-3002cdd18bac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6947-0063-7975-9ead-3002cdd18bac_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6947-0063-7975-9ead-3002cdd18bac" xlink:to="loc_us-gaap_EquityComponentDomain_019e6947-0063-7975-9ead-3002cdd18bac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6947-0063-7975-9ead-3002cdd18bac" xlink:to="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019e6947-0063-7efc-96f1-f6521fbe8362" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019e6947-0063-7efc-96f1-f6521fbe8362" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-7633-a11e-56c1f73e24d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019e6947-0063-7efc-96f1-f6521fbe8362" xlink:to="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-7633-a11e-56c1f73e24d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_019e6947-0063-7290-86b7-167c546e2dc1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019e6947-0063-7efc-96f1-f6521fbe8362" xlink:to="loc_us-gaap_AccumulatedForeignCurrencyAdjustmentAttributableToNoncontrollingInterestMember_019e6947-0063-7290-86b7-167c546e2dc1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019e6947-0063-7194-b371-466f5fc86136" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019e6947-0063-7194-b371-466f5fc86136" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-79f8-ab54-97451cd4c9a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019e6947-0063-7194-b371-466f5fc86136" xlink:to="loc_us-gaap_AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-79f8-ab54-97451cd4c9a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_019e6947-0063-7010-9e2e-365e76252eb7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019e6947-0063-7194-b371-466f5fc86136" xlink:to="loc_us-gaap_AccumulatedNetInvestmentGainLossAttributableToNoncontrollingInterestMember_019e6947-0063-7010-9e2e-365e76252eb7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019e6947-0063-71aa-9418-f587e7b6f35a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019e6947-0063-71aa-9418-f587e7b6f35a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-75fe-b150-42384d29f0b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019e6947-0063-71aa-9418-f587e7b6f35a" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-75fe-b150-42384d29f0b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_019e6947-0063-79be-80b9-74b5a91ba43c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019e6947-0063-71aa-9418-f587e7b6f35a" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentAttributableToNoncontrollingInterestMember_019e6947-0063-79be-80b9-74b5a91ba43c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AOCIDebtValuationAdjustmentParentMember_019e6947-0063-7f44-9a6a-62595a861d55" xlink:href="ms-20260630.xsd#ms_AOCIDebtValuationAdjustmentParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_ms_AOCIDebtValuationAdjustmentParentMember_019e6947-0063-7f44-9a6a-62595a861d55" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AOCIDebtValuationAdjustmentIncludingNoncontrollingInterestMember_019e6947-0063-7e96-8a6d-341b370db2b9" xlink:href="ms-20260630.xsd#ms_AOCIDebtValuationAdjustmentIncludingNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AOCIDebtValuationAdjustmentParentMember_019e6947-0063-7f44-9a6a-62595a861d55" xlink:to="loc_ms_AOCIDebtValuationAdjustmentIncludingNoncontrollingInterestMember_019e6947-0063-7e96-8a6d-341b370db2b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AOCIDebtValuationAdjustmentNoncontrollingInterestMember_019e6947-0063-78c8-b712-2d4def69a054" xlink:href="ms-20260630.xsd#ms_AOCIDebtValuationAdjustmentNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_ms_AOCIDebtValuationAdjustmentParentMember_019e6947-0063-7f44-9a6a-62595a861d55" xlink:to="loc_ms_AOCIDebtValuationAdjustmentNoncontrollingInterestMember_019e6947-0063-78c8-b712-2d4def69a054" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentParentMember_019e6947-0063-752f-8c41-6a63f8f4cbf6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentParentMember_019e6947-0063-752f-8c41-6a63f8f4cbf6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossDerivativeQualifyingAsHedgeExcludedComponentIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-78b9-b4e3-bd9c241e46d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossDerivativeQualifyingAsHedgeExcludedComponentIncludingPortionAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentParentMember_019e6947-0063-752f-8c41-6a63f8f4cbf6" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossDerivativeQualifyingAsHedgeExcludedComponentIncludingPortionAttributableToNoncontrollingInterestMember_019e6947-0063-78b9-b4e3-bd9c241e46d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentNoncontrollingInterestMember_019e6947-0063-7c10-bbfd-dea70c35698a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentParentMember_019e6947-0063-752f-8c41-6a63f8f4cbf6" xlink:to="loc_us-gaap_AociDerivativeQualifyingAsHedgeExcludedComponentNoncontrollingInterestMember_019e6947-0063-7c10-bbfd-dea70c35698a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6947-0063-7b29-bdc1-c46bff52fbd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6947-0063-7b29-bdc1-c46bff52fbd4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AociAttributableToNoncontrollingInterestMember_019e6947-0063-79ed-af03-72bd321c5dac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AociAttributableToNoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6947-0063-7603-8a7e-563e903d6576" xlink:to="loc_us-gaap_AociAttributableToNoncontrollingInterestMember_019e6947-0063-79ed-af03-72bd321c5dac" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6947-0063-737d-ae83-9850f9a076b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019e6947-0063-7259-b917-8b9bb88ecbbc" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6947-0063-737d-ae83-9850f9a076b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e6947-0063-711d-bd34-a050f0994c76" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6947-0063-737d-ae83-9850f9a076b5" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e6947-0063-711d-bd34-a050f0994c76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciEquityMethodInvestmentAfterTaxAbstract_019e6947-0063-70fc-a833-103e69938c9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OciEquityMethodInvestmentAfterTaxAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6947-0063-737d-ae83-9850f9a076b5" xlink:to="loc_us-gaap_OciEquityMethodInvestmentAfterTaxAbstract_019e6947-0063-70fc-a833-103e69938c9e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_019e6947-0063-7a59-b593-4f2a6a78724d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OciEquityMethodInvestmentAfterTaxAbstract_019e6947-0063-70fc-a833-103e69938c9e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_019e6947-0063-7a59-b593-4f2a6a78724d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_019e6947-0063-72f6-96cd-4c726c71f4d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OciEquityMethodInvestmentAfterTaxAbstract_019e6947-0063-70fc-a833-103e69938c9e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsTax_019e6947-0063-72f6-96cd-4c726c71f4d1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_019e6947-0063-75da-91dc-d6d37326f6a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OciEquityMethodInvestmentAfterTaxAbstract_019e6947-0063-70fc-a833-103e69938c9e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_019e6947-0063-75da-91dc-d6d37326f6a8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_019e6947-0063-76c3-84c2-2a87ed10d84c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6947-0063-737d-ae83-9850f9a076b5" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_019e6947-0063-76c3-84c2-2a87ed10d84c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_019e6947-0063-72ee-b560-bfd246f3a8a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_019e6947-0063-76c3-84c2-2a87ed10d84c" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_019e6947-0063-72ee-b560-bfd246f3a8a0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_019e6947-0063-743c-b411-ba3e76f8625b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAociCurrentPeriodTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_019e6947-0063-76c3-84c2-2a87ed10d84c" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_019e6947-0063-743c-b411-ba3e76f8625b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_019e6947-0063-70a2-b65c-b5d0a5ff4dc3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_019e6947-0063-76c3-84c2-2a87ed10d84c" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_019e6947-0063-70a2-b65c-b5d0a5ff4dc3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e6947-0063-78fe-b6c4-d6462666eede" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6947-0063-737d-ae83-9850f9a076b5" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e6947-0063-78fe-b6c4-d6462666eede" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e6947-0063-786d-af2e-4fc3acb2d980" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationSelectedFinancialInformationbyBusinessSegmentDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#SegmentGeographicandRevenueInformationSelectedFinancialInformationbyBusinessSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationSelectedFinancialInformationbyBusinessSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0063-7831-86c8-39519f763844" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0063-7831-86c8-39519f763844" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0063-70ba-8679-be2f276ebc29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0063-7831-86c8-39519f763844" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0063-70ba-8679-be2f276ebc29" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6947-0063-70ba-8679-be2f276ebc29_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0063-70ba-8679-be2f276ebc29" xlink:to="loc_us-gaap_SegmentDomain_019e6947-0063-70ba-8679-be2f276ebc29_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6947-0063-703c-85c3-fbea07aa848f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0063-70ba-8679-be2f276ebc29" xlink:to="loc_us-gaap_SegmentDomain_019e6947-0063-703c-85c3-fbea07aa848f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InstitutionalSecuritiesSegmentMember_019e6947-0063-704f-adc3-c7fcede2dba6" xlink:href="ms-20260630.xsd#ms_InstitutionalSecuritiesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0063-703c-85c3-fbea07aa848f" xlink:to="loc_ms_InstitutionalSecuritiesSegmentMember_019e6947-0063-704f-adc3-c7fcede2dba6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_WealthManagementSegmentMember_019e6947-0063-7dec-8d9c-5777ec9ba4d0" xlink:href="ms-20260630.xsd#ms_WealthManagementSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0063-703c-85c3-fbea07aa848f" xlink:to="loc_ms_WealthManagementSegmentMember_019e6947-0063-7dec-8d9c-5777ec9ba4d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentManagementSegmentMember_019e6947-0063-71bb-9279-e36c800492f4" xlink:href="ms-20260630.xsd#ms_InvestmentManagementSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0063-703c-85c3-fbea07aa848f" xlink:to="loc_ms_InvestmentManagementSegmentMember_019e6947-0063-71bb-9279-e36c800492f4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019e6947-0063-7713-845c-cd35a094b28d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0063-7831-86c8-39519f763844" xlink:to="loc_srt_ConsolidationItemsAxis_019e6947-0063-7713-845c-cd35a094b28d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6947-0063-7713-845c-cd35a094b28d_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019e6947-0063-7713-845c-cd35a094b28d" xlink:to="loc_srt_ConsolidationItemsDomain_019e6947-0063-7713-845c-cd35a094b28d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6947-0063-7860-b8ef-41653318fa00" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019e6947-0063-7713-845c-cd35a094b28d" xlink:to="loc_srt_ConsolidationItemsDomain_019e6947-0063-7860-b8ef-41653318fa00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019e6947-0064-7dce-87a1-3ff8e4834912" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e6947-0063-7860-b8ef-41653318fa00" xlink:to="loc_us-gaap_OperatingSegmentsMember_019e6947-0064-7dce-87a1-3ff8e4834912" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_019e6947-0064-71f7-b18a-fcbff6b137a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e6947-0063-7860-b8ef-41653318fa00" xlink:to="loc_us-gaap_IntersegmentEliminationMember_019e6947-0064-71f7-b18a-fcbff6b137a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentBankingRevenue_019e6947-0064-70ca-b69b-85a67f67c910" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentBankingRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_InvestmentBankingRevenue_019e6947-0064-70ca-b69b-85a67f67c910" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingGainsLosses_019e6947-0064-7eaf-8d8f-ea29452e86fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_TradingGainsLosses_019e6947-0064-7eaf-8d8f-ea29452e86fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrincipalInvestmentGainsLosses_019e6947-0064-72f0-bb93-242fbc277e67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrincipalInvestmentGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_PrincipalInvestmentGainsLosses_019e6947-0064-72f0-bb93-242fbc277e67" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BrokerageCommissionsRevenue_019e6947-0064-7e95-98ab-452d78d133af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BrokerageCommissionsRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_BrokerageCommissionsRevenue_019e6947-0064-7e95-98ab-452d78d133af" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_AssetManagementFees_019e6947-0064-7428-bd7b-91d60aff2fd5" xlink:href="ms-20260630.xsd#ms_AssetManagementFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_ms_AssetManagementFees_019e6947-0064-7428-bd7b-91d60aff2fd5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeOtherOperatingIncome_019e6947-0064-7752-9c9c-07ab96cc5a78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoninterestIncomeOtherOperatingIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_NoninterestIncomeOtherOperatingIncome_019e6947-0064-7752-9c9c-07ab96cc5a78" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome_019e6947-0064-7540-8d0d-8f735b48ff33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoninterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_NoninterestIncome_019e6947-0064-7540-8d0d-8f735b48ff33" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating_019e6947-0064-7c74-a785-05407b95e3d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_InterestAndDividendIncomeOperating_019e6947-0064-7c74-a785-05407b95e3d4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating_019e6947-0064-790a-93a2-2377d21d90f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_InterestExpenseOperating_019e6947-0064-790a-93a2-2377d21d90f3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_019e6947-0064-7aa7-b441-f5bc2f163330" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_019e6947-0064-7aa7-b441-f5bc2f163330" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesNetOfInterestExpense_019e6947-0064-7e3a-9ef4-e0d510059321" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenuesNetOfInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_RevenuesNetOfInterestExpense_019e6947-0064-7e3a-9ef4-e0d510059321" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_FinancingReceivableAndOffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_019e6947-0064-7005-8891-2fdce9e1b402" xlink:href="ms-20260630.xsd#ms_FinancingReceivableAndOffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_ms_FinancingReceivableAndOffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_019e6947-0064-7005-8891-2fdce9e1b402" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_019e6947-0064-7abb-bff9-28654bee82da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_LaborAndRelatedExpense_019e6947-0064-7abb-bff9-28654bee82da" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_NoninterestExpenseExcludingLaborAndRelatedExpense_019e6947-0064-70bb-bc3d-eadcc3ffbef3" xlink:href="ms-20260630.xsd#ms_NoninterestExpenseExcludingLaborAndRelatedExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_ms_NoninterestExpenseExcludingLaborAndRelatedExpense_019e6947-0064-70bb-bc3d-eadcc3ffbef3" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpense_019e6947-0064-7ed1-a43d-1a878c1f25e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoninterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_NoninterestExpense_019e6947-0064-7ed1-a43d-1a878c1f25e1" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e6947-0064-7ec2-a9ef-93426cfd89e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e6947-0064-7ec2-a9ef-93426cfd89e6" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019e6947-0064-7c1a-9378-6374f4ec5e00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019e6947-0064-7c1a-9378-6374f4ec5e00" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019e7547-b659-761b-8b3a-3dcc2886d068" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019e7547-b659-761b-8b3a-3dcc2886d068" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e6947-0064-78c4-8f31-f05f7b66fed0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_ProfitLoss_019e6947-0064-78c4-8f31-f05f7b66fed0" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNonredeemableNoncontrollingInterest_019e6947-0064-7ea7-9d2c-968281ea2611" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNonredeemableNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNonredeemableNoncontrollingInterest_019e6947-0064-7ea7-9d2c-968281ea2611" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e6947-0064-7065-9fa6-790d58dd96a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_us-gaap_NetIncomeLoss_019e6947-0064-7065-9fa6-790d58dd96a8" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_EffectiveIncomeTaxRateReconciliationPreTaxMarginPercent_019e6947-0064-72c1-8f9d-3e95b79a7830" xlink:href="ms-20260630.xsd#ms_EffectiveIncomeTaxRateReconciliationPreTaxMarginPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-788b-aa90-bc3b8d7a62b2" xlink:to="loc_ms_EffectiveIncomeTaxRateReconciliationPreTaxMarginPercent_019e6947-0064-72c1-8f9d-3e95b79a7830" xlink:type="arc" order="21"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationInstitutionalSecuritiesInvestmentBankingRevenuesDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#SegmentGeographicandRevenueInformationInstitutionalSecuritiesInvestmentBankingRevenuesDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationInstitutionalSecuritiesInvestmentBankingRevenuesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6947-0064-73a4-93c2-579aa7d875aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6947-0064-74a2-8669-9d6a760a523e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6947-0064-73a4-93c2-579aa7d875aa" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6947-0064-74a2-8669-9d6a760a523e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7a92-8202-62b1f8470627" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6947-0064-74a2-8669-9d6a760a523e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7a92-8202-62b1f8470627" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6947-0064-7a92-8202-62b1f8470627_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7a92-8202-62b1f8470627" xlink:to="loc_us-gaap_SegmentDomain_019e6947-0064-7a92-8202-62b1f8470627_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6947-0064-7ba4-acac-9546664f179d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7a92-8202-62b1f8470627" xlink:to="loc_us-gaap_SegmentDomain_019e6947-0064-7ba4-acac-9546664f179d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InstitutionalSecuritiesSegmentMember_019e6947-0064-77c1-acf6-0b84781f9c87" xlink:href="ms-20260630.xsd#ms_InstitutionalSecuritiesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0064-7ba4-acac-9546664f179d" xlink:to="loc_ms_InstitutionalSecuritiesSegmentMember_019e6947-0064-77c1-acf6-0b84781f9c87" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019e6947-0064-788d-9b12-61f31bd22055" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6947-0064-74a2-8669-9d6a760a523e" xlink:to="loc_srt_ConsolidationItemsAxis_019e6947-0064-788d-9b12-61f31bd22055" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6947-0064-788d-9b12-61f31bd22055_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019e6947-0064-788d-9b12-61f31bd22055" xlink:to="loc_srt_ConsolidationItemsDomain_019e6947-0064-788d-9b12-61f31bd22055_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6947-0064-7b1b-b808-8e70f0a2091d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019e6947-0064-788d-9b12-61f31bd22055" xlink:to="loc_srt_ConsolidationItemsDomain_019e6947-0064-7b1b-b808-8e70f0a2091d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019e6947-0064-7cb9-80c8-e6f88acc66ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e6947-0064-7b1b-b808-8e70f0a2091d" xlink:to="loc_us-gaap_OperatingSegmentsMember_019e6947-0064-7cb9-80c8-e6f88acc66ab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019e6947-0064-7ce3-8a6b-17db64e8c003" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6947-0064-74a2-8669-9d6a760a523e" xlink:to="loc_srt_ProductOrServiceAxis_019e6947-0064-7ce3-8a6b-17db64e8c003" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019e6947-0064-7ce3-8a6b-17db64e8c003_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019e6947-0064-7ce3-8a6b-17db64e8c003" xlink:to="loc_srt_ProductsAndServicesDomain_019e6947-0064-7ce3-8a6b-17db64e8c003_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019e6947-0064-79e5-9710-1a4a01e97008" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019e6947-0064-7ce3-8a6b-17db64e8c003" xlink:to="loc_srt_ProductsAndServicesDomain_019e6947-0064-79e5-9710-1a4a01e97008" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAdviceMember_019e6947-0064-7d67-b8e4-71c415b0e5b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAdviceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6947-0064-79e5-9710-1a4a01e97008" xlink:to="loc_us-gaap_InvestmentAdviceMember_019e6947-0064-7d67-b8e4-71c415b0e5b7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_UnderwritingMember_019e6947-0064-7b25-b67c-01fa3d9bfe9e" xlink:href="ms-20260630.xsd#ms_UnderwritingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6947-0064-79e5-9710-1a4a01e97008" xlink:to="loc_ms_UnderwritingMember_019e6947-0064-7b25-b67c-01fa3d9bfe9e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentBankingRevenue_019e6947-0064-7309-87f2-923ac59dc23f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentBankingRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6947-0064-73a4-93c2-579aa7d875aa" xlink:to="loc_us-gaap_InvestmentBankingRevenue_019e6947-0064-7309-87f2-923ac59dc23f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_ProportionOfInvestmentBankingRevenueRecognizedUnderNewAccountingPronouncement_019e6947-0064-778c-a819-75a227cdd0ca" xlink:href="ms-20260630.xsd#ms_ProportionOfInvestmentBankingRevenueRecognizedUnderNewAccountingPronouncement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6947-0064-73a4-93c2-579aa7d875aa" xlink:to="loc_ms_ProportionOfInvestmentBankingRevenueRecognizedUnderNewAccountingPronouncement_019e6947-0064-778c-a819-75a227cdd0ca" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationTradingRevenuesbyProductTypeDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#SegmentGeographicandRevenueInformationTradingRevenuesbyProductTypeDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationTradingRevenuesbyProductTypeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019e6947-0064-77da-a7b8-576a538bbdee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019e6947-0064-7b0d-a4a6-6080e333a5c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e6947-0064-77da-a7b8-576a538bbdee" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019e6947-0064-7b0d-a4a6-6080e333a5c1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6947-0064-7d7b-909f-80e08ec7bdf7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019e6947-0064-7b0d-a4a6-6080e333a5c1" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6947-0064-7d7b-909f-80e08ec7bdf7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7d7b-909f-80e08ec7bdf7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6947-0064-7d7b-909f-80e08ec7bdf7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7d7b-909f-80e08ec7bdf7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6947-0064-7d7b-909f-80e08ec7bdf7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e6947-0064-7c20-8f4d-57918dd27f17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:to="loc_us-gaap_InterestRateContractMember_019e6947-0064-7c20-8f4d-57918dd27f17" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019e6947-0064-7888-b427-344673249a27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019e6947-0064-7888-b427-344673249a27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_EquityAndIndexContractMember_019e6947-0064-7c87-9b6d-43d246ab527c" xlink:href="ms-20260630.xsd#ms_EquityAndIndexContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:to="loc_ms_EquityAndIndexContractMember_019e6947-0064-7c87-9b6d-43d246ab527c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_CommodityAndOtherContractsMember_019e6947-0064-7dbf-b8d9-890ef8f9084e" xlink:href="ms-20260630.xsd#ms_CommodityAndOtherContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:to="loc_ms_CommodityAndOtherContractsMember_019e6947-0064-7dbf-b8d9-890ef8f9084e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019e6947-0064-7540-a0b7-264485662dab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6947-0064-7e31-8eb1-0695b8e79f4c" xlink:to="loc_us-gaap_CreditRiskContractMember_019e6947-0064-7540-a0b7-264485662dab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingGainsLosses_019e6947-0064-7782-8388-442c29b13456" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e6947-0064-77da-a7b8-576a538bbdee" xlink:to="loc_us-gaap_TradingGainsLosses_019e6947-0064-7782-8388-442c29b13456" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationNetRevenuesbyRegionDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#SegmentGeographicandRevenueInformationNetRevenuesbyRegionDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationNetRevenuesbyRegionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-7d98-ae14-821d1f41a261" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0064-76c6-bc31-479851e51652" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-7d98-ae14-821d1f41a261" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0064-76c6-bc31-479851e51652" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019e6947-0064-73a9-b94c-e53dbfdeeada" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0064-76c6-bc31-479851e51652" xlink:to="loc_srt_StatementGeographicalAxis_019e6947-0064-73a9-b94c-e53dbfdeeada" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019e6947-0064-73a9-b94c-e53dbfdeeada_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019e6947-0064-73a9-b94c-e53dbfdeeada" xlink:to="loc_srt_SegmentGeographicalDomain_019e6947-0064-73a9-b94c-e53dbfdeeada_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019e6947-0064-7244-9a82-e05fe9aa9a03" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019e6947-0064-73a9-b94c-e53dbfdeeada" xlink:to="loc_srt_SegmentGeographicalDomain_019e6947-0064-7244-9a82-e05fe9aa9a03" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AmericasMember_019e6947-0064-7a65-8c13-8ee97b458896" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AmericasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019e6947-0064-7244-9a82-e05fe9aa9a03" xlink:to="loc_srt_AmericasMember_019e6947-0064-7a65-8c13-8ee97b458896" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EMEAMember_019e6947-0064-7522-bbdc-d5a8352bab61" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EMEAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019e6947-0064-7244-9a82-e05fe9aa9a03" xlink:to="loc_us-gaap_EMEAMember_019e6947-0064-7522-bbdc-d5a8352bab61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaMember_019e6947-0064-758a-88f8-8f4aabe573d6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AsiaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019e6947-0064-7244-9a82-e05fe9aa9a03" xlink:to="loc_srt_AsiaMember_019e6947-0064-758a-88f8-8f4aabe573d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesNetOfInterestExpense_019e6947-0064-76b0-99e1-a78937f5819d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenuesNetOfInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-7d98-ae14-821d1f41a261" xlink:to="loc_us-gaap_RevenuesNetOfInterestExpense_019e6947-0064-76b0-99e1-a78937f5819d" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationAssetsbyBusinessSegmentDetails" xlink:type="simple" xlink:href="ms-20260630.xsd#SegmentGeographicandRevenueInformationAssetsbyBusinessSegmentDetails"/>
  <link:definitionLink xlink:role="http://www.morganstanley.com/role/SegmentGeographicandRevenueInformationAssetsbyBusinessSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-7303-bef8-ea9dd1099168" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0064-7ba9-958d-3a29fb7d01b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-7303-bef8-ea9dd1099168" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0064-7ba9-958d-3a29fb7d01b2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7d85-bd66-b6bdab527742" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6947-0064-7ba9-958d-3a29fb7d01b2" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7d85-bd66-b6bdab527742" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6947-0064-7d85-bd66-b6bdab527742_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7d85-bd66-b6bdab527742" xlink:to="loc_us-gaap_SegmentDomain_019e6947-0064-7d85-bd66-b6bdab527742_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6947-0064-7bca-a1d1-2da969ef704f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6947-0064-7d85-bd66-b6bdab527742" xlink:to="loc_us-gaap_SegmentDomain_019e6947-0064-7bca-a1d1-2da969ef704f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InstitutionalSecuritiesSegmentMember_019e6947-0064-733f-bd37-58c6213dd0bf" xlink:href="ms-20260630.xsd#ms_InstitutionalSecuritiesSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0064-7bca-a1d1-2da969ef704f" xlink:to="loc_ms_InstitutionalSecuritiesSegmentMember_019e6947-0064-733f-bd37-58c6213dd0bf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_WealthManagementSegmentMember_019e6947-0064-7888-9f2a-a0842ff8392f" xlink:href="ms-20260630.xsd#ms_WealthManagementSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0064-7bca-a1d1-2da969ef704f" xlink:to="loc_ms_WealthManagementSegmentMember_019e6947-0064-7888-9f2a-a0842ff8392f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_ms_InvestmentManagementSegmentMember_019e6947-0064-7bbf-bb9c-f8d940f22992" xlink:href="ms-20260630.xsd#ms_InvestmentManagementSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6947-0064-7bca-a1d1-2da969ef704f" xlink:to="loc_ms_InvestmentManagementSegmentMember_019e6947-0064-7bbf-bb9c-f8d940f22992" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e6947-0064-735d-bd88-bf4ab5cd35d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6947-0064-7303-bef8-ea9dd1099168" xlink:to="loc_us-gaap_Assets_019e6947-0064-735d-bd88-bf4ab5cd35d5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-roles-2026.xsd#eedm1"/>
  <link:definitionLink xlink:role="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfCashFlowsAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:to="loc_us-gaap_DepreciationAndAmortization" xlink:type="arc" order="31"/>
  </link:definitionLink>
</link:linkbase>
