<?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">
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    <isConfidential>false</isConfidential>
    <filerInfo>

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          <ccc>XXXXXXXX</ccc>
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        <classId>C000043620</classId>
        <classId>C000043619</classId>
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      <regFileNumber>811-07584</regFileNumber>
      <regCik>0000899148</regCik>
      <regLei>5493004D62WV1EDNTU07</regLei>
      <regStreet1>702 King Farm Blvd., Suite 200</regStreet1>
      <regCity>Rockville</regCity>
      <regStateConditional regCountry="US" regState="US-MD"/>
      <regZipOrPostalCode>20850</regZipOrPostalCode>
      <regPhone>301-296-5100</regPhone>
      <seriesName>Inverse High Yield Strategy Fund</seriesName>
      <seriesId>S000015882</seriesId>
      <seriesLei>SCQPAL0SXRZDT2DWGE91</seriesLei>
      <repPdEnd>2020-03-31</repPdEnd>
      <repPdDate>2019-12-31</repPdDate>
      <isFinalFiling>N</isFinalFiling>
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      <totLiabs>5629.48</totLiabs>
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      <assetsInvested>0</assetsInvested>
      <amtPayOneYrBanksBorr>0</amtPayOneYrBanksBorr>
      <amtPayOneYrCtrldComp>0</amtPayOneYrCtrldComp>
      <amtPayOneYrOthAffil>0</amtPayOneYrOthAffil>
      <amtPayOneYrOther>0</amtPayOneYrOther>
      <amtPayAftOneYrBanksBorr>0</amtPayAftOneYrBanksBorr>
      <amtPayAftOneYrCtrldComp>0</amtPayAftOneYrCtrldComp>
      <amtPayAftOneYrOthAffil>0</amtPayAftOneYrOthAffil>
      <amtPayAftOneYrOther>0</amtPayAftOneYrOther>
      <delayDeliv>0</delayDeliv>
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      <invstOrSec>
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      <invstOrSec>
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              <invstCat>UST</invstCat>
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      </invstOrSec>
    </invstOrSecs>
    <signature>
      <ncom:dateSigned>2020-01-30</ncom:dateSigned>
      <ncom:nameOfApplicant>Rydex Series Funds</ncom:nameOfApplicant>
      <ncom:signature>John Sullivan</ncom:signature>
      <ncom:signerName>John Sullivan</ncom:signerName>
      <ncom:title>CFO</ncom:title>
    </signature>
  </formData>
  <documents>XXXX</documents>
</edgarSubmission>
