<?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>0001181556</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>BUTLER-LEVIN REVOCABLE TRUST U/ADTD 05/27/2003</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Director</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>20000</noOfUnitsSold>
            <aggregateMarketValue>537400.00</aggregateMarketValue>
            <noOfUnitsOutstanding>79719473</noOfUnitsOutstanding>
            <approxSaleDate>04/03/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>11/19/2013</acquiredDate>
            <natureOfAcquisitionTransaction>Previously Exercised Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>20000</amountOfSecuritiesAcquired>
            <paymentDate>11/19/2013</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for ARTHUR A LEVIN</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>03/19/2024</saleDate>
            <amountOfSecuritiesSold>5000</amountOfSecuritiesSold>
            <grossProceeds>119847.50</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for ARTHUR A LEVIN</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>03/12/2024</saleDate>
            <amountOfSecuritiesSold>27641</amountOfSecuritiesSold>
            <grossProceeds>609114.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>04/03/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>05/26/2023</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Arthur A Levin</signature>
        </noticeSignature>
    </formData>
</edgarSubmission>
[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 4818}]
144
0001181556
XXXXXXXX
LIVE
0001599901
AVIDITY BIOSCIENCES INC
001-39321
10578 Science Center Drive, Suite 125
San Diego
CA
92121
8584017900
BUTLER-LEVIN REVOCABLE TRUST U/ADTD 05/27/2003
Director
COMMON
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
20000
537400.00
79719473
04/03/2024
NASDAQ
Common
11/19/2013
Previously Exercised Options
Issuer
N
20000
11/19/2013
Cash
N
10b5-1 Sales for ARTHUR A LEVIN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
03/19/2024
5000
119847.50
10b5-1 Sales for ARTHUR A LEVIN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
03/12/2024
27641
609114.00
04/03/2024
05/26/2023
/s/ Arthur A Levin