content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
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        <filer>
          <filerCredentials>
            <cik>0001856565</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
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      <issuerInfo>
        <issuerCik>0001447362</issuerCik>
        <issuerName>Castle Biosciences, Inc.</issuerName>
        <secFileNumber>001-38984</secFileNumber>
        <issuerAddress>
          <com:street1>505 S. Friendswood Drive, Suite 401</com:street1>
          <com:city>Friendswood</com:city>
          <com:stateOrCountry>TX</com:stateOrCountry>
          <com:zipCode>77546</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>866-788-9007</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Kristen Oelschager</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>J.P. Morgan Securities LLC</name>
          <address>
            <com:street1>390 Madison Avenue</com:street1>
            <com:street2>6th Floor</com:street2>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10017</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>24407</noOfUnitsSold>
        <aggregateMarketValue>531340</aggregateMarketValue>
        <noOfUnitsOutstanding>27607183</noOfUnitsOutstanding>
        <approxSaleDate>07/01/2024</approxSaleDate>
        <securitiesExchangeName>Nasdaq</securitiesExchangeName>
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        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>12/10/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Unit</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1234</amountOfSecuritiesAcquired>
        <paymentDate>12/10/2021</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>12/10/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Unit</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>5586</amountOfSecuritiesAcquired>
        <paymentDate>12/10/2022</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>12/09/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Unit</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>11755</amountOfSecuritiesAcquired>
        <paymentDate>12/09/2023</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>12/10/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Unit</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>5832</amountOfSecuritiesAcquired>
        <paymentDate>12/10/2023</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>07/01/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>03/15/2024</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Kristen Oelschager.</signature>
      </noticeSignature>
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text: 144
  0001856565
  XXXXXXXX
  LIVE
  0001447362
  Castle Biosciences, Inc.
  001-38984
  505 S. Friendswood Drive, Suite 401
  Friendswood
  TX
  77546
  866-788-9007
  Kristen Oelschager
  Officer
  Common Stock
  J.P. Morgan Securities LLC
  390 Madison Avenue
  6th Floor
  New York
  NY
  10017
  24407
  531340
  27607183
  07/01/2024
  Nasdaq
  Common
  12/10/2021
  Restricted Stock Unit
  Issuer
  N
  1234
  12/10/2021
  NA
  Common
  12/10/2022
  Restricted Stock Unit
  Issuer
  N
  5586
  12/10/2022
  NA
  Common
  12/09/2023
  Restricted Stock Unit
  Issuer
  N
  11755
  12/09/2023
  NA
  Common
  12/10/2023
  Restricted Stock Unit
  Issuer
  N
  5832
  12/10/2023
  NA
  Y
  07/01/2024
  03/15/2024
  /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Kristen Oelschager.