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        <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>Northwestern Mutual Series Fund, Inc. - High Yield Bond Portfolio</name>
        <lei>KUVC5M5XHVXDKYES4T32</lei>
        <title>Northwestern Mutual Series Fund, Inc. - High Yield Bond Portfolio</title>
        <cusip>668140742</cusip>
        <identifiers>
          <isin value="US6681407424"/>
        </identifiers>
        <balance>25844614.84300000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>19409305.75000000</valUSD>
        <pctVal>6.325788126121</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>Exxon Mobil Corp</name>
        <lei>J3WHBG0MTS7O8ZVMDC91</lei>
        <title>Exxon Mobil Corp</title>
        <cusip>30229AQB8</cusip>
        <identifiers>
          <other otherDesc="CUSIP" value="30229AQB8"/>
        </identifiers>
        <balance>1000000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>999741.39000000</valUSD>
        <pctVal>0.325830933651</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2021-03-11</maturityDt>
          <couponKind>None</couponKind>
          <annualizedRt>0.00000000</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>Northwestern Mutual Series Fund, Inc. - Short-Term Bond Portfolio.</name>
        <lei>BEEDB5U9NNUVQYFFEL15</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Short-Term Bond Portfolio.</title>
        <cusip>668140601</cusip>
        <identifiers>
          <isin value="US6681406012"/>
        </identifiers>
        <balance>1279187.20900000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1376405.44000000</valUSD>
        <pctVal>0.448591479841</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>Chevron Corp</name>
        <lei>N/A</lei>
        <title>Chevron Corp</title>
        <cusip>16677JP26</cusip>
        <identifiers>
          <other otherDesc="CUSIP" value="16677JP26"/>
        </identifiers>
        <balance>500000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>499944.54000000</valUSD>
        <pctVal>0.162939534035</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2021-02-02</maturityDt>
          <couponKind>None</couponKind>
          <annualizedRt>0.00000000</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>Northwestern Mutual Series Fund, Inc. - Research International Core Portfolio</name>
        <lei>549300ZQ5NCCGE71IX14</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Research International Core Portfolio</title>
        <cusip>668140403</cusip>
        <identifiers>
          <isin value="US6681404033"/>
        </identifiers>
        <balance>21448168.55000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>25330287.06000000</valUSD>
        <pctVal>8.255526044016</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>Northwestern Mutual Series Fund, Inc. - Mid Cap Value Portfolio</name>
        <lei>8TRVIGMWHSWZVXP7PI34</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Mid Cap Value Portfolio</title>
        <cusip>668140783</cusip>
        <identifiers>
          <isin value="US6681407838"/>
        </identifiers>
        <balance>8930016.37800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>14743457.04000000</valUSD>
        <pctVal>4.805117023911</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>Northwestern Mutual Series Fund, Inc. - Emerging Markets Equity Portfolio</name>
        <lei>549300B2SFS01R9MCJ10</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Emerging Markets Equity Portfolio</title>
        <cusip>668140502</cusip>
        <identifiers>
          <isin value="US6681405022"/>
        </identifiers>
        <balance>2660673.49900000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3703657.51000000</valUSD>
        <pctVal>1.207078346940</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>Northwestern Mutual Series Fund, Inc. - Large Co Value Por</name>
        <lei>6UWSQM9V60QIAUKWH425</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Large Co Value Por</title>
        <cusip>668140106</cusip>
        <identifiers>
          <isin value="US6681401062"/>
        </identifiers>
        <balance>12746050.03400000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12758796.08000000</valUSD>
        <pctVal>4.158285813312</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>iShares Core MSCI Emerging Markets ETF</name>
        <lei>5493007C24Z3ZDJ0VD06</lei>
        <title>iShares Core MSCI Emerging Markets ETF</title>
        <cusip>46434G103</cusip>
        <identifiers>
          <isin value="US46434G1031"/>
        </identifiers>
        <balance>19000.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1178760.00000000</valUSD>
        <pctVal>0.384175823060</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>iShares Core S&amp;P Mid-Cap ETF</name>
        <lei>549300ODQWH5PC0IUZ78</lei>
        <title>iShares Core S&amp;P Mid-Cap ETF</title>
        <cusip>464287507</cusip>
        <identifiers>
          <isin value="US4642875078"/>
        </identifiers>
        <balance>13550.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3114196.50000000</valUSD>
        <pctVal>1.014964033018</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>Chevron Corp</name>
        <lei>N/A</lei>
        <title>Chevron Corp</title>
        <cusip>16677JN51</cusip>
        <identifiers>
          <other otherDesc="CUSIP" value="16677JN51"/>
        </identifiers>
        <balance>500000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>499990.97000000</valUSD>
        <pctVal>0.162954666278</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</assetCat>
        <issuerCat>CORP</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2021-01-05</maturityDt>
          <couponKind>None</couponKind>
          <annualizedRt>0.00000000</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>Northwestern Mutual Series Fund, Inc. - Small Cap Value Portfolio</name>
        <lei>5493006BEZYY47A02J59</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Small Cap Value Portfolio</title>
        <cusip>668140817</cusip>
        <identifiers>
          <isin value="US6681408174"/>
        </identifiers>
        <balance>3205663.98800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7058872.10000000</valUSD>
        <pctVal>2.300593843445</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>Northwestern Mutual Series Fund, Inc. - Small Cap Growth Stock Portfolio</name>
        <lei>YTR2S467AP5XPLF6CQ13</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Small Cap Growth Stock Portfolio</title>
        <cusip>668140825</cusip>
        <identifiers>
          <isin value="US6681408257"/>
        </identifiers>
        <balance>2085885.31800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7135813.67000000</valUSD>
        <pctVal>2.325670272049</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>FED HOME LN DISCOUNT NT</name>
        <lei>2549001DPIFGXC1TOL40</lei>
        <title>Federal Home Loan Bank Discount Notes</title>
        <cusip>313385AU0</cusip>
        <identifiers>
          <isin value="US313385AU06"/>
        </identifiers>
        <balance>1000000.00000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>999970.83000000</valUSD>
        <pctVal>0.325905711639</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>USGSE</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2021-01-19</maturityDt>
          <couponKind>None</couponKind>
          <annualizedRt>0.00000000</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>Northwestern Mutual Series Fund, Inc. - Growth Stock Portfolio</name>
        <lei>SZG5ML0R3BIC0KK1SI27</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Growth Stock Portfolio</title>
        <cusip>668140858</cusip>
        <identifiers>
          <isin value="US6681408588"/>
        </identifiers>
        <balance>4808218.83000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>17328820.66000000</valUSD>
        <pctVal>5.647726373248</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>Northwestern Mutual Series Fund, Inc. - Equity Income Portfolio</name>
        <lei>549300X5C6L2WKRYCD90</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Equity Income Portfolio</title>
        <cusip>668140767</cusip>
        <identifiers>
          <isin value="US6681407671"/>
        </identifiers>
        <balance>7886266.93800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12894046.44000000</valUSD>
        <pctVal>4.202365963955</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>Northwestern Mutual Series Fund, Inc. - Large Cap Blend Portfolio</name>
        <lei>549300J8IDGQV6XROU84</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Large Cap Blend Portfolio</title>
        <cusip>668140205</cusip>
        <identifiers>
          <isin value="US6681402052"/>
        </identifiers>
        <balance>10640826.08500000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>13343595.91000000</valUSD>
        <pctVal>4.348880977736</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>Northwestern Mutual Series Fund, Inc. - Mid Cap Growth Stock Portfolio</name>
        <lei>LIP0ME8UWTR611J45283</lei>
        <title>Northwestern Mutual Series Fund, Inc. - Mid Cap Growth Stock Portfolio</title>
        <cusip>668140866</cusip>
        <identifiers>
          <isin value="US6681408661"/>
        </identifiers>
        <balance>3856674.96500000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15785370.63000000</valUSD>
        <pctVal>5.144692519344</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>
    </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>2021-01-26</ncom:dateSigned>
      <ncom:nameOfApplicant>NORTHWESTERN MUTUAL SERIES FUND INC</ncom:nameOfApplicant>
      <ncom:signature>Barbara Courtney</ncom:signature>
      <ncom:signerName>Barbara Courtney</ncom:signerName>
      <ncom:title>Controller and Chief Accounting Officer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
