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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019fcd2e-f27f-71bc-97a1-34bca6f581af,g:60a5e42c-538f-4e5c-88c3-927ecf52787e-->
<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.amcor.com/role/Cover" xlink:type="simple" xlink:href="amcr-20260812.xsd#Cover"/>
  <link:definitionLink xlink:role="http://www.amcor.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsLineItems_019fcd2e-f27f-799f-ae42-7b62a4586ad4" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsTable_019fcd2e-f27f-78d9-a96b-1361bead210a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityListingsLineItems_019fcd2e-f27f-799f-ae42-7b62a4586ad4" xlink:to="loc_dei_EntityListingsTable_019fcd2e-f27f-78d9-a96b-1361bead210a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019fcd2e-f27f-78f1-a4fe-b3c18fd04b01" 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_EntityListingsTable_019fcd2e-f27f-78d9-a96b-1361bead210a" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019fcd2e-f27f-78f1-a4fe-b3c18fd04b01" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-78f1-a4fe-b3c18fd04b01_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_019fcd2e-f27f-78f1-a4fe-b3c18fd04b01" xlink:to="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-78f1-a4fe-b3c18fd04b01_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" 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_019fcd2e-f27f-78f1-a4fe-b3c18fd04b01" xlink:to="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019fcd2e-f27f-7a79-8b35-3f9aaea59d8e" 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_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:to="loc_us-gaap_CommonStockMember_019fcd2e-f27f-7a79-8b35-3f9aaea59d8e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_amcr_GuaranteedSeniorNotesDue2027Member_019fcd2e-f27f-73cf-814c-7c02f122d22d" xlink:href="amcr-20260812.xsd#amcr_GuaranteedSeniorNotesDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:to="loc_amcr_GuaranteedSeniorNotesDue2027Member_019fcd2e-f27f-73cf-814c-7c02f122d22d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_amcr_A5.450GuaranteedSeniorNotesDue2029Member_019fcd2e-f27f-72a2-a900-1e8557bab4ef" xlink:href="amcr-20260812.xsd#amcr_A5.450GuaranteedSeniorNotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:to="loc_amcr_A5.450GuaranteedSeniorNotesDue2029Member_019fcd2e-f27f-72a2-a900-1e8557bab4ef" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_amcr_A3.950GuaranteedSeniorNotesDue2032Member_019fcd2e-f27f-729d-9eae-f18075507678" xlink:href="amcr-20260812.xsd#amcr_A3.950GuaranteedSeniorNotesDue2032Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:to="loc_amcr_A3.950GuaranteedSeniorNotesDue2032Member_019fcd2e-f27f-729d-9eae-f18075507678" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_amcr_A3.200GuaranteedSeniorNotesDue2029Member_019fcd3d-9837-7e64-b024-723190b7c561" xlink:href="amcr-20260812.xsd#amcr_A3.200GuaranteedSeniorNotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:to="loc_amcr_A3.200GuaranteedSeniorNotesDue2029Member_019fcd3d-9837-7e64-b024-723190b7c561" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_amcr_A3.750GuaranteedSeniorNotesDue2033Member_019fcd40-c190-7948-ba66-5c1a43ae862b" xlink:href="amcr-20260812.xsd#amcr_A3.750GuaranteedSeniorNotesDue2033Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019fcd2e-f27f-7aaa-8a88-d81099184b10" xlink:to="loc_amcr_A3.750GuaranteedSeniorNotesDue2033Member_019fcd40-c190-7948-ba66-5c1a43ae862b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019fcd2e-f27f-7c82-abe2-8457f2616fbe" 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_EntityListingsLineItems_019fcd2e-f27f-799f-ae42-7b62a4586ad4" xlink:to="loc_dei_Security12bTitle_019fcd2e-f27f-7c82-abe2-8457f2616fbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019fcd2e-f27f-7adb-8312-22a433dabd17" 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_EntityListingsLineItems_019fcd2e-f27f-799f-ae42-7b62a4586ad4" xlink:to="loc_dei_TradingSymbol_019fcd2e-f27f-7adb-8312-22a433dabd17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019fcd2e-f27f-736e-910b-b5038934b239" 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_EntityListingsLineItems_019fcd2e-f27f-799f-ae42-7b62a4586ad4" xlink:to="loc_dei_SecurityExchangeName_019fcd2e-f27f-736e-910b-b5038934b239" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CountryRegion_019fcd2e-f27f-7aa1-a42a-1bede5b40bd1" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CountryRegion"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityListingsLineItems_019fcd2e-f27f-799f-ae42-7b62a4586ad4" xlink:to="loc_dei_CountryRegion_019fcd2e-f27f-7aa1-a42a-1bede5b40bd1" xlink:type="arc" order="3"/>
  </link:definitionLink>
</link:linkbase>
