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          <ccc>XXXXXXXX</ccc>
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        <classId>C000043619</classId>
        <classId>C000043620</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>2021-03-31</repPdEnd>
      <repPdDate>2020-12-31</repPdDate>
      <isFinalFiling>N</isFinalFiling>
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    <signature>
      <ncom:dateSigned>2021-02-01</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>
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</edgarSubmission>
