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        <valUSD>12860450.75000000</valUSD>
        <pctVal>5.263603928282</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>Northrop Grumman Corp</name>
        <lei>RIMU48P07456QXSO0R61</lei>
        <title>Northrop Grumman Corp</title>
        <cusip>666807102</cusip>
        <identifiers>
          <isin value="US6668071029"/>
        </identifiers>
        <balance>17615.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>8807147.70000000</valUSD>
        <pctVal>3.604643268875</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>Apple Inc</name>
        <lei>HWUPKR0MPOU8FGXBT394</lei>
        <title>Apple Inc</title>
        <cusip>037833100</cusip>
        <identifiers>
          <isin value="US0378331005"/>
        </identifiers>
        <balance>39156.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>8033636.52000000</valUSD>
        <pctVal>3.288055882883</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>Danaher Corp</name>
        <lei>S4BKK9OTCEWQ3YHPFM11</lei>
        <title>Danaher Corp</title>
        <cusip>235851102</cusip>
        <identifiers>
          <isin value="US2358511028"/>
        </identifiers>
        <balance>48562.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>9592937.48000000</valUSD>
        <pctVal>3.926256115362</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>S&amp;P Global Inc</name>
        <lei>Y6X4K52KMJMZE7I7MY94</lei>
        <title>S&amp;P Global Inc</title>
        <cusip>78409V104</cusip>
        <identifiers>
          <isin value="US78409V1044"/>
        </identifiers>
        <balance>19986.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>10538417.94000000</valUSD>
        <pctVal>4.313228139913</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>Eli Lilly &amp; Co</name>
        <lei>FRDRIPF3EKNDJ2CQJL29</lei>
        <title>Eli Lilly &amp; Co</title>
        <cusip>532457108</cusip>
        <identifiers>
          <isin value="US5324571083"/>
        </identifiers>
        <balance>9886.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7706433.58000000</valUSD>
        <pctVal>3.154136262660</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>American Express Co</name>
        <lei>R4PP93JZOLY261QX3811</lei>
        <title>American Express Co</title>
        <cusip>025816109</cusip>
        <identifiers>
          <isin value="US0258161092"/>
        </identifiers>
        <balance>31907.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>10177694.86000000</valUSD>
        <pctVal>4.165589191806</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>
