<?xml version="1.0" encoding="UTF-8"?><ns2:edgarSubmission xmlns:com="http://www.sec.gov/edgar/common" xmlns:ns2="http://www.sec.gov/edgar/ownership">
    <ns2:headerData>
        <ns2:submissionType>144</ns2:submissionType>
        <ns2:filerInfo>
            <ns2:filer>
                <ns2:filerCredentials>
                    <ns2:cik>0001236397</ns2:cik>
                    <ns2:ccc>XXXXXXXX</ns2:ccc>
                </ns2:filerCredentials>
            </ns2:filer>
            <ns2:liveTestFlag>LIVE</ns2:liveTestFlag>



        </ns2:filerInfo>
    </ns2:headerData>
    <ns2:formData>
        <ns2:issuerInfo>
            <ns2:issuerCik>0001447362</ns2:issuerCik>
            <ns2:issuerName>Castle Biosciences, Inc.</ns2:issuerName>
            <ns2:secFileNumber>001-38984</ns2:secFileNumber>
            <ns2:issuerAddress>
                <com:street1>505 S FRIENDSWOOD DR</com:street1>
                <com:street2>SUITE 401</com:street2>
                <com:city>FRIENDSWOOD</com:city>
                <com:stateOrCountry>TX</com:stateOrCountry>
                <com:zipCode>77546</com:zipCode>
            </ns2:issuerAddress>
            <ns2:issuerContactPhone>1-866-788-9007</ns2:issuerContactPhone>
            <ns2:nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Daniel Bradbury</ns2:nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <ns2:relationshipsToIssuer>
                <ns2:relationshipToIssuer>Other: Affiliate</ns2:relationshipToIssuer>
            </ns2:relationshipsToIssuer>
        </ns2:issuerInfo>
        <ns2:securitiesInformation>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:brokerOrMarketmakerDetails>
                <ns2:name>Goldman Sachs &amp; Co. LLC</ns2:name>
                <ns2:address>
                    <com:street1>200 West Street</com:street1>
                    <com:city>New York</com:city>
                    <com:stateOrCountry>NY</com:stateOrCountry>
                    <com:zipCode>10282</com:zipCode>
                </ns2:address>
            </ns2:brokerOrMarketmakerDetails>
            <ns2:noOfUnitsSold>46646</ns2:noOfUnitsSold>
            <ns2:aggregateMarketValue>1086851.8</ns2:aggregateMarketValue>
            <ns2:noOfUnitsOutstanding>26910548</ns2:noOfUnitsOutstanding>
            <ns2:approxSaleDate>02/05/2024</ns2:approxSaleDate>
            <ns2:securitiesExchangeName>NASD</ns2:securitiesExchangeName>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/03/2018</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Private Transaction</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>13458</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>01/03/2018</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>12/08/2020</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Daniel Bradbury</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>01/30/2019</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>15934</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>01/30/2019</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
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            <ns2:acquiredDate>12/08/2020</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Gift</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Daniel Bradbury</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>Y</ns2:isGiftTransaction>
            <ns2:donarAcquiredDate>01/30/2019</ns2:donarAcquiredDate>
            <ns2:amountOfSecuritiesAcquired>15925</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>01/30/2019</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:acquiredDate>06/06/2018</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Private Transaction</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1329</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>06/06/2018</ns2:paymentDate>
            <ns2:natureOfPayment>N/A</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>N</ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Daniel M. Bradbury Irrevocable Descendants Trust</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>12/04/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>1482</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>29764.34</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Annette E. Bradbury Irrevocable Descendants Trust</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
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            <ns2:amountOfSecuritiesSold>1483</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>29784.42</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>BioBrit, LLC</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
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            <ns2:grossProceeds>27615.36</ns2:grossProceeds>
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        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Daniel M. Bradbury Irrevocable Descendants Trust</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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                </ns2:address>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>12/13/2023</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>399</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>7997.08</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Annette E. Bradbury Irrevocable Descendants Trust</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
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                    <com:stateOrCountry>TX</com:stateOrCountry>
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        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
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            <ns2:saleDate>12/13/2023</ns2:saleDate>
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        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Daniel M. Bradbury Irrevocable Descendants Trust</ns2:name>
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            <ns2:grossProceeds>35441.54</ns2:grossProceeds>
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        <ns2:securitiesSoldInPast3Months>
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            <ns2:grossProceeds>35461.89</ns2:grossProceeds>
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        <ns2:securitiesSoldInPast3Months>
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        <ns2:securitiesSoldInPast3Months>
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            <ns2:grossProceeds>1361.02</ns2:grossProceeds>
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        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Annette E. Bradbury Irrevocable Descendants Trust</ns2:name>
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        <ns2:securitiesSoldInPast3Months>
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                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
            </ns2:sellerDetails>
            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>01/04/2024</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>6222</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>126899.56</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>The Annette E. Bradbury Irrevocable Descendants Trust</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>01/04/2024</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>6225</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>126960.74</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:securitiesSoldInPast3Months>
            <ns2:sellerDetails>
                <ns2:name>BioBrit, LLC</ns2:name>
                <ns2:address>
                    <com:street1>505 S FRIENDSWOOD DR</com:street1>
                    <com:street2>SUITE 401</com:street2>
                    <com:city>FRIENDSWOOD</com:city>
                    <com:stateOrCountry>TX</com:stateOrCountry>
                    <com:zipCode>77546</com:zipCode>
                </ns2:address>
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            <ns2:securitiesClassTitle>Common</ns2:securitiesClassTitle>
            <ns2:saleDate>01/04/2024</ns2:saleDate>
            <ns2:amountOfSecuritiesSold>5776</ns2:amountOfSecuritiesSold>
            <ns2:grossProceeds>117803.25</ns2:grossProceeds>
        </ns2:securitiesSoldInPast3Months>
        <ns2:remarks>Total number of shares to be sold includes 14,787 shares by BioBrit, LLC, 15,925 shares by The Daniel M. Bradbury Irrevocable Descendants Trust, 15,934  shares by The Annette E. Bradbury Irrevocable Descendants Trust. The sales set forth herein are made in connection with a selling plan dated 8/22/2023, that is intended to comply with Rule 105-1 (c).</ns2:remarks>
        <ns2:noticeSignature>
            <ns2:noticeDate>02/05/2024</ns2:noticeDate>
            <ns2:planAdoptionDates>
                <ns2:planAdoptionDate>08/22/2023</ns2:planAdoptionDate>
            </ns2:planAdoptionDates>
            <ns2:signature>Goldman Sachs &amp; Co. LLC on behalf of Daniel Bradbury</ns2:signature>
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144
0001236397
XXXXXXXX
LIVE
0001447362
Castle Biosciences, Inc.
001-38984
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
1-866-788-9007
Daniel Bradbury
Other: Affiliate
Common
Goldman Sachs & Co. LLC
200 West Street
New York
NY
10282
46646
1086851.8
26910548
02/05/2024
NASD
Common
01/03/2018
Private Transaction
Issuer
N
13458
01/03/2018
N/A
Common
12/08/2020
Gift
Daniel Bradbury
Y
01/30/2019
15934
01/30/2019
N/A
Common
12/08/2020
Gift
Daniel Bradbury
Y
01/30/2019
15925
01/30/2019
N/A
Common
06/06/2018
Private Transaction
Issuer
N
1329
06/06/2018
N/A
N
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/04/2023
1482
29764.34
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/04/2023
1483
29784.42
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/04/2023
1375
27615.36
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/13/2023
399
7997.08
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/13/2023
399
7997.08
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/13/2023
370
7415.84
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
01/05/2024
1741
35441.54
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
01/05/2024
1742
35461.89
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
01/05/2024
1617
32917.27
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/06/2023
68
1361.02
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/06/2023
68
1361.02
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/06/2023
64
1280.96
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/08/2023
2347
47158.51
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/08/2023
2349
47198.69
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/08/2023
2179
43782.86
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/01/2023
3259
65357.62
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/01/2023
3261
65397.72
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/01/2023
3025
60664.86
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/12/2023
410
8205.45
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/12/2023
410
8205.45
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
12/12/2023
380
7605.05
The Daniel M. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
01/04/2024
6222
126899.56
The Annette E. Bradbury Irrevocable Descendants Trust
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
01/04/2024
6225
126960.74
BioBrit, LLC
505 S FRIENDSWOOD DR
SUITE 401
FRIENDSWOOD
TX
77546
Common
01/04/2024
5776
117803.25
Total number of shares to be sold includes 14,787 shares by BioBrit, LLC, 15,925 shares by The Daniel M. Bradbury Irrevocable Descendants Trust, 15,934  shares by The Annette E. Bradbury Irrevocable Descendants Trust. The sales set forth herein are made in connection with a selling plan dated 8/22/2023, that is intended to comply with Rule 105-1 (c).
02/05/2024
08/22/2023
Goldman Sachs & Co. LLC on behalf of Daniel Bradbury