<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0101</schemaVersion>

    <submissionType>EFFECT</submissionType>

    <act>33</act>

    <testOrLive>LIVE</testOrLive>

    <effectiveData>
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        <finalEffectivenessDispTime>15:45:00</finalEffectivenessDispTime>
        <form>N-14</form>
        <filer>
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            <entityName>JANUS INVESTMENT FUND</entityName>
            <fileNumber>333-215394</fileNumber>
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                    <targetEntityName>JANUS INVESTMENT FUND</targetEntityName>
                    <targetSeriesId>S000010487</targetSeriesId>
                    <targetSeriesName>Janus Twenty Fund</targetSeriesName>
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                    <acquiringSeriesName>Janus Forty Fund</acquiringSeriesName>
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                    <targetEntityName>JANUS INVESTMENT FUND</targetEntityName>
                    <targetSeriesId>S000010487</targetSeriesId>
                    <targetSeriesName>Janus Twenty Fund</targetSeriesName>
                    <targetClassContractId>C000083532</targetClassContractId>
                    <targetClassContractName>Class D</targetClassContractName>
                </merger>
            </seriesClassContractData>
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    </effectiveData>
</edgarSubmission>
