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          <clearedCentCparty centralCounterparty="Fixed Income Clearing Corp" isCleared="Y"/>
          <isTriParty>N</isTriParty>
          <repurchaseRt>2.75000000</repurchaseRt>
          <maturityDt>2025-07-01</maturityDt>
          <repurchaseCollaterals>
            <repurchaseCollateral>
              <principalAmt>2831200.00000000</principalAmt>
              <principalCd>USD</principalCd>
              <collateralVal>2883994.26000000</collateralVal>
              <collateralCd>USD</collateralCd>
              <invstCat>UST</invstCat>
            </repurchaseCollateral>
          </repurchaseCollaterals>
        </repurchaseAgrmt>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Roche Holding AG</name>
        <lei>549300U41AUUVOAAOB37</lei>
        <title>Roche Holding AG</title>
        <cusip>771195104</cusip>
        <identifiers>
          <isin value="US7711951043"/>
        </identifiers>
        <balance>43196.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1760668.96000000</valUSD>
        <pctVal>0.805923212939</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>CH</invCountry>

        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <loanByFundCondition isLoanByFund="Y" loanVal="1743060.64000000"/>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Netflix Inc</name>
        <lei>549300Y7VHGU0I7CE873</lei>
        <title>Netflix Inc</title>
        <cusip>64110L106</cusip>
        <identifiers>
          <isin value="US64110L1061"/>
        </identifiers>
        <balance>13112.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>17558672.56000000</valUSD>
        <pctVal>8.037252956691</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Intuitive Surgical Inc</name>
        <lei>54930052SRG011710797</lei>
        <title>Intuitive Surgical Inc</title>
        <cusip>46120E602</cusip>
        <identifiers>
          <isin value="US46120E6023"/>
        </identifiers>
        <balance>5797.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3150147.77000000</valUSD>
        <pctVal>1.441938984392</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Tesla Inc</name>
        <lei>54930043XZGB27CTOV49</lei>
        <title>Tesla Inc</title>
        <cusip>88160R101</cusip>
        <identifiers>
          <isin value="US88160R1014"/>
        </identifiers>
        <balance>44271.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>14063125.86000000</valUSD>
        <pctVal>6.437212124798</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Yum China Holdings Inc</name>
        <lei>529900DO9BYZ7VA3K502</lei>
        <title>Yum China Holdings Inc</title>
        <cusip>98850P109</cusip>
        <identifiers>
          <isin value="US98850P1093"/>
        </identifiers>
        <balance>11948.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>534195.08000000</valUSD>
        <pctVal>0.244520818502</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>

        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>FactSet Research Systems Inc</name>
        <lei>549300ZSJE7NBK6K9P30</lei>
        <title>FactSet Research Systems Inc</title>
        <cusip>303075105</cusip>
        <identifiers>
          <isin value="US3030751057"/>
        </identifiers>
        <balance>5003.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2237741.84000000</valUSD>
        <pctVal>1.024297090705</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Deere &amp; Co</name>
        <lei>PWFTNG3EI0Y73OXWDH08</lei>
        <title>Deere &amp; Co</title>
        <cusip>244199105</cusip>
        <identifiers>
          <isin value="US2441991054"/>
        </identifiers>
        <balance>4539.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2308036.11000000</valUSD>
        <pctVal>1.056473374388</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Meta Platforms Inc</name>
        <lei>BQ4BKCS1HXDV9HN80Z93</lei>
        <title>Meta Platforms Inc</title>
        <cusip>30303M102</cusip>
        <identifiers>
          <isin value="US30303M1027"/>
        </identifiers>
        <balance>25151.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>18563701.59000000</valUSD>
        <pctVal>8.497291864263</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Oracle Corp</name>
        <lei>1Z4GXXU7ZHVWFCD8TV52</lei>
        <title>Oracle Corp</title>
        <cusip>68389X105</cusip>
        <identifiers>
          <isin value="US68389X1054"/>
        </identifiers>
        <balance>56096.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12264268.48000000</valUSD>
        <pctVal>5.613808661543</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Boeing Co/The</name>
        <lei>RVHJWBXLJ1RFUBSY1F30</lei>
        <title>Boeing Co/The</title>
        <cusip>097023105</cusip>
        <identifiers>
          <isin value="US0970231058"/>
        </identifiers>
        <balance>49565.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>10385354.45000000</valUSD>
        <pctVal>4.753760312707</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Autodesk Inc</name>
        <lei>FRKKVKAIQEF3FCSTPG55</lei>
        <title>Autodesk Inc</title>
        <cusip>052769106</cusip>
        <identifiers>
          <isin value="US0527691069"/>
        </identifiers>
        <balance>19149.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5927955.93000000</valUSD>
        <pctVal>2.713444377000</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Starbucks Corp</name>
        <lei>OQSJ1DU9TAOC51A47K68</lei>
        <title>Starbucks Corp</title>
        <cusip>855244109</cusip>
        <identifiers>
          <isin value="US8552441094"/>
        </identifiers>
        <balance>32022.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2934175.86000000</valUSD>
        <pctVal>1.343080664307</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Yum! Brands Inc</name>
        <lei>549300JE8XHZZ7OHN517</lei>
        <title>Yum! Brands Inc</title>
        <cusip>988498101</cusip>
        <identifiers>
          <isin value="US9884981013"/>
        </identifiers>
        <balance>13141.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1947233.38000000</valUSD>
        <pctVal>0.891320638692</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>QUALCOMM Inc</name>
        <lei>H1J8DDZKZP6H7RWC0H53</lei>
        <title>QUALCOMM Inc</title>
        <cusip>747525103</cusip>
        <identifiers>
          <isin value="US7475251036"/>
        </identifiers>
        <balance>15305.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2437474.30000000</valUSD>
        <pctVal>1.115722014724</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Shopify Inc</name>
        <lei>549300HGQ43STJLLP808</lei>
        <title>Shopify Inc</title>
        <cusip>82509L107</cusip>
        <identifiers>
          <isin value="CA82509L1076"/>
        </identifiers>
        <balance>46667.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5383038.45000000</valUSD>
        <pctVal>2.464015519988</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>CA</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Regeneron Pharmaceuticals Inc</name>
        <lei>549300RCBFWIRX3HYQ56</lei>
        <title>Regeneron Pharmaceuticals Inc</title>
        <cusip>75886F107</cusip>
        <identifiers>
          <isin value="US75886F1075"/>
        </identifiers>
        <balance>6520.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3423000.00000000</valUSD>
        <pctVal>1.566833527804</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Novartis AG</name>
        <lei>5493007HIVTX6SY6XD66</lei>
        <title>Novartis AG</title>
        <cusip>66987V109</cusip>
        <identifiers>
          <isin value="US66987V1098"/>
        </identifiers>
        <balance>18989.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2297858.89000000</valUSD>
        <pctVal>1.051814884901</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>CH</invCountry>

        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Amazon.com Inc</name>
        <lei>ZXTILKJKG63JELOEG630</lei>
        <title>Amazon.com Inc</title>
        <cusip>023135106</cusip>
        <identifiers>
          <isin value="US0231351067"/>
        </identifiers>
        <balance>58743.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12887626.77000000</valUSD>
        <pctVal>5.899142774487</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>SEI Investments Co</name>
        <lei>5LJTIFADGZ6XH1RVOC11</lei>
        <title>SEI Investments Co</title>
        <cusip>784117103</cusip>
        <identifiers>
          <isin value="US7841171033"/>
        </identifiers>
        <balance>28499.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2560920.14000000</valUSD>
        <pctVal>1.172227735139</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <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"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2025-07-28</ncom:dateSigned>
      <ncom:nameOfApplicant>MML SERIES INVESTMENT FUND</ncom:nameOfApplicant>
      <ncom:signature>Renee Hitchcock</ncom:signature>
      <ncom:signerName>Renee Hitchcock</ncom:signerName>
      <ncom:title>CFO and Treasurer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
