<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:ns2="http://www.sec.gov/edgar/common">
    <headerData>
        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001841990</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <issuerInfo>
            <issuerCik>0001599901</issuerCik>
            <issuerName>AVIDITY BIOSCIENCES INC</issuerName>
            <secFileNumber>001-39321</secFileNumber>
            <issuerAddress>
                <ns2:street1>10578 Science Center Drive, Suite 125</ns2:street1>
                <ns2:city>San Diego</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>92121</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>8584017900</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>WILLIAM MICHAEL FLANAGAN</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>111394</noOfUnitsSold>
            <aggregateMarketValue>4543761.26</aggregateMarketValue>
            <noOfUnitsOutstanding>109801397</noOfUnitsOutstanding>
            <approxSaleDate>09/11/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>09/11/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Stock Units</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>14894</amountOfSecuritiesAcquired>
            <paymentDate>09/11/2024</paymentDate>
            <natureOfPayment>N/A</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>09/11/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>96500</amountOfSecuritiesAcquired>
            <paymentDate>09/11/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>WILLIAM MICHAEL FLANAGAN</name>
                <address>
                    <ns2:street1>10578 Science Center Drive, Suite 125</ns2:street1>
                    <ns2:city>San Diego</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>92121</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>06/18/2024</saleDate>
            <amountOfSecuritiesSold>10106</amountOfSecuritiesSold>
            <grossProceeds>395444.75</grossProceeds>
        </securitiesSoldInPast3Months>
        <remarks>The securities to be sold were and will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment were and will be the dates of exercise/sale.&#13;
</remarks>
        <noticeSignature>
            <noticeDate>09/11/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>06/12/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ William Michael Flanagan</signature>
        </noticeSignature>
    </formData>
</edgarSubmission>
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144
0001841990
XXXXXXXX
LIVE
0001599901
AVIDITY BIOSCIENCES INC
001-39321
10578 Science Center Drive, Suite 125
San Diego
CA
92121
8584017900
WILLIAM MICHAEL FLANAGAN
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
111394
4543761.26
109801397
09/11/2024
NASDAQ
Common
09/11/2024
Performance Stock Units
Issuer
N
14894
09/11/2024
N/A
Common
09/11/2024
Exercise of Stock Options
Issuer
N
96500
09/11/2024
Cash
N
WILLIAM MICHAEL FLANAGAN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
06/18/2024
10106
395444.75
The securities to be sold were and will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment were and will be the dates of exercise/sale.
09/11/2024
06/12/2024
/s/ William Michael Flanagan