<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/nport" xmlns:com="http://www.sec.gov/edgar/common" xmlns:ncom="http://www.sec.gov/edgar/nportcommon" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sec.gov/edgar/nport eis_NPORT_Filer.xsd">
  <headerData>
    <submissionType>NPORT-P</submissionType>
    <isConfidential>false</isConfidential>
    <filerInfo>
      
      <filer>
        <issuerCredentials>
          <cik>0000355437</cik>
          <ccc>XXXXXXXX</ccc>
        </issuerCredentials>
      </filer>
      
      
      <seriesClassInfo>
        <seriesId>S000054156</seriesId>
        <classId>C000170210</classId>
      </seriesClassInfo>
      
      
    </filerInfo>
  </headerData>
  <formData>
    <genInfo>
      <regName>DFA INVESTMENT DIMENSIONS GROUP INC</regName>
      <regFileNumber>811-03258</regFileNumber>
      <regCik>0000355437</regCik>
      <regLei>549300XGRTBJCE41BD26</regLei>
      <regStreet1>6300 BEE CAVE ROAD</regStreet1>
      <regStreet2>BUILDING ONE</regStreet2>
      <regCity>AUSTIN</regCity>
      <regStateConditional regCountry="US" regState="US-TX"/>
      <regZipOrPostalCode>78746</regZipOrPostalCode>
      <regPhone>512-306-7400</regPhone>
      <seriesName>DFA Diversified Fixed Income Portfolio</seriesName>
      <seriesId>S000054156</seriesId>
      <seriesLei>549300VV3QSNEWJBLF55</seriesLei>
      <repPdEnd>2026-10-31</repPdEnd>
      <repPdDate>2026-04-30</repPdDate>
      <isFinalFiling>N</isFinalFiling>
    </genInfo>
    <fundInfo>
      <totAssets>1678034494.86</totAssets>
      <totLiabs>237923.45</totLiabs>
      <netAssets>1677796571.41</netAssets>
      <assetsAttrMiscSec>0.00000000</assetsAttrMiscSec>
      <assetsInvested>0.00000000</assetsInvested>
      <amtPayOneYrBanksBorr>0.00000000</amtPayOneYrBanksBorr>
      <amtPayOneYrCtrldComp>0.00000000</amtPayOneYrCtrldComp>
      <amtPayOneYrOthAffil>0.00000000</amtPayOneYrOthAffil>
      <amtPayOneYrOther>0.00000000</amtPayOneYrOther>
      <amtPayAftOneYrBanksBorr>0.00000000</amtPayAftOneYrBanksBorr>
      <amtPayAftOneYrCtrldComp>0.00000000</amtPayAftOneYrCtrldComp>
      <amtPayAftOneYrOthAffil>0.00000000</amtPayAftOneYrOthAffil>
      <amtPayAftOneYrOther>0.00000000</amtPayAftOneYrOther>
      <delayDeliv>0.00000000</delayDeliv>
      <standByCommit>0.00000000</standByCommit>
      <liquidPref>0.00000000</liquidPref>
      <cshNotRptdInCorD>0.00000000</cshNotRptdInCorD>
      <isNonCashCollateral>N</isNonCashCollateral>
      <returnInfo>
        <monthlyTotReturns>
          <monthlyTotReturn classId="C000170210" rtn1="1.39000000" rtn2="-1.19000000" rtn3="0.32000000"/>
        </monthlyTotReturns>
        <othMon1 netRealizedGain="0.00000000" netUnrealizedAppr="22077188.10000000"/>
        <othMon2 netRealizedGain="-137489.42000000" netUnrealizedAppr="-29164487.43000000"/>
        <othMon3 netRealizedGain="-295971.35000000" netUnrealizedAppr="4222613.53000000"/>
      </returnInfo>
      <mon1Flow redemption="24803353.79000000" reinvestment="0.00000000" sales="25164015.00000000"/>
      <mon2Flow redemption="30166849.67000000" reinvestment="8457366.57000000" sales="18186906.32000000"/>
      <mon3Flow redemption="21010698.94000000" reinvestment="0.00000000" sales="21305711.21000000"/>
      
      
    </fundInfo>
    <invstOrSecs>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Inflation-Indexed Notes</title>
        <cusip>91282CCM1</cusip>
        <identifiers>
          <isin value="US91282CCM10"/>
        </identifiers>
        <balance>52486628.30000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>49431616.28000000</valUSD>
        <pctVal>2.946222272850</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2031-07-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>0.13000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Inflation-Indexed Notes</title>
        <cusip>91282CJY8</cusip>
        <identifiers>
          <isin value="US91282CJY84"/>
        </identifiers>
        <balance>82977630.45000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>83267478.78000000</valUSD>
        <pctVal>4.962906719377</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2034-01-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>1.75000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Inflation-Indexed Bonds</title>
        <cusip>912810FQ6</cusip>
        <identifiers>
          <isin value="US912810FQ68"/>
        </identifiers>
        <balance>73013348.75000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>80988703.43000000</valUSD>
        <pctVal>4.827087193409</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2032-04-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>3.38000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>DFA Intermediate Government Fixed Income Portfolio</name>
        <lei>5493002LBS0SC8B6NR25</lei>
        <title>DFA Intermediate Government Fixed Income Portfolio</title>
        <cusip>233203876</cusip>
        <identifiers>
          <isin value="US2332038767"/>
        </identifiers>
        <balance>75038800.96000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>838183406.77000000</valUSD>
        <pctVal>49.95739179903</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>State Street Global Advisors</name>
        <lei>549300BZ5TGIFZUZDZ37</lei>
        <title>State Street Institutional U.S. Government Money Market Fund</title>
        <cusip>857492706</cusip>
        <identifiers>
          <isin value="US8574927062"/>
        </identifiers>
        <balance>4419131.05000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4419131.05000000</valUSD>
        <pctVal>0.263388966535</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Inflation-Indexed Notes</title>
        <cusip>91282CML2</cusip>
        <identifiers>
          <isin value="US91282CML27"/>
        </identifiers>
        <balance>33078474.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>33886868.24000000</valUSD>
        <pctVal>2.019724489693</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2035-01-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>2.13000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>DFA Two-Year Global Fixed Income Portfolio</name>
        <lei>549300PFM0BC0V0V1O39</lei>
        <title>DFA Two-Year Global Fixed Income Portfolio</title>
        <cusip>233203645</cusip>
        <identifiers>
          <isin value="US2332036456"/>
        </identifiers>
        <balance>51263554.80000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>502382837.07000000</valUSD>
        <pctVal>29.94301249810</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>U.S. Treasury Inflation-Indexed Notes</title>
        <cusip>91282CDX6</cusip>
        <identifiers>
          <isin value="US91282CDX65"/>
        </identifiers>
        <balance>90988202.60000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>84515379.21000000</valUSD>
        <pctVal>5.037284057564</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>
        
        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2032-01-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>0.13000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
      <explntrNote note="For purposes of Item C.6 identifying restricted securities,  a security that is subject to Rule 144A under the Securities Act of 1933, as amended, is identified as a restricted security only if the fund cannot sell the security to qualified institutional buyers at the report date due to the restrictions under Rule 144A." noteItem="C.6"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2026-05-19</ncom:dateSigned>
      <ncom:nameOfApplicant>DFA INVESTMENT DIMENSIONS GROUP INC</ncom:nameOfApplicant>
      <ncom:signature>Randy Olson</ncom:signature>
      <ncom:signerName>Randy Olson</ncom:signerName>
      <ncom:title>Vice President</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
