content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
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  <submissionType>144</submissionType>
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  <filerCredentials>
  <cik>0002005875</cik>
  <ccc>XXXXXXXX</ccc>
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  <liveTestFlag>LIVE</liveTestFlag>
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  <formData>
  <issuerInfo>
  <issuerCik>0001719714</issuerCik>
  <issuerName>Mereo BioPharma Group plc</issuerName>
  <secFileNumber>001-38452</secFileNumber>
  <issuerAddress>
  <street1 xmlns="http://www.sec.gov/edgar/common">4th Floor, One Cavendish Place</street1>
  <city xmlns="http://www.sec.gov/edgar/common">London</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">X0</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">W1G 0QF</zipCode>
  </issuerAddress>
  <issuerContactPhone>44-333 023 7300</issuerContactPhone>
  <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Alexandra Hughes-Wilson</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
  <relationshipsToIssuer>
  <relationshipToIssuer>Officer</relationshipToIssuer>
  </relationshipsToIssuer>
  </issuerInfo>
  <securitiesInformation>
  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <brokerOrMarketmakerDetails>
  <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
  <address>
  <street1 xmlns="http://www.sec.gov/edgar/common">1 New York Plaza</street1>
  <street2 xmlns="http://www.sec.gov/edgar/common">38th Floor</street2>
  <city xmlns="http://www.sec.gov/edgar/common">New York</city>
  <stateOrCountry xmlns="http://www.sec.gov/edgar/common">NY</stateOrCountry>
  <zipCode xmlns="http://www.sec.gov/edgar/common">10004</zipCode>
  </address>
  </brokerOrMarketmakerDetails>
  <noOfUnitsSold>100432</noOfUnitsSold>
  <aggregateMarketValue>297505.97</aggregateMarketValue>
  <noOfUnitsOutstanding>702493754</noOfUnitsOutstanding>
  <approxSaleDate>05/22/2024</approxSaleDate>
  <securitiesExchangeName>Nasdaq</securitiesExchangeName>
  </securitiesInformation>
  <securitiesToBeSold>
  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <acquiredDate>05/22/2024</acquiredDate>
  <natureOfAcquisitionTransaction>Share Option Exercise</natureOfAcquisitionTransaction>
  <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
  <isGiftTransaction>N</isGiftTransaction>
  <amountOfSecuritiesAcquired>50350</amountOfSecuritiesAcquired>
  <paymentDate>05/22/2024</paymentDate>
  <natureOfPayment>Cash</natureOfPayment>
  </securitiesToBeSold>
  <securitiesToBeSold>
  <securitiesClassTitle>American Depositary Shares Representing Ordinary Shares</securitiesClassTitle>
  <acquiredDate>05/22/2024</acquiredDate>
  <natureOfAcquisitionTransaction>Share Option Exercise</natureOfAcquisitionTransaction>
  <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
  <isGiftTransaction>N</isGiftTransaction>
  <amountOfSecuritiesAcquired>50082</amountOfSecuritiesAcquired>
  <paymentDate>05/22/2024</paymentDate>
  <natureOfPayment>Cash</natureOfPayment>
  </securitiesToBeSold>
  <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
  <remarks>The number of shares to be sold is in the form of American Depositary Shares ("ADSs"). The number of shares outstanding is in the form of ordinary shares.
  
  Each ADS represents 5 ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.</remarks>
  <noticeSignature>
  <noticeDate>05/23/2024</noticeDate>
  <signature>/s/ Alexandra Hughes-Wilson</signature>
  </noticeSignature>
  </formData>
  </edgarSubmission>
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text: 144
  0002005875
  XXXXXXXX
  LIVE
  0001719714
  Mereo BioPharma Group plc
  001-38452
  4th Floor, One Cavendish Place
  London
  X0
  W1G 0QF
  44-333 023 7300
  Alexandra Hughes-Wilson
  Officer
  American Depositary Shares Representing Ordinary Shares
  Morgan Stanley Smith Barney LLC Executive Financial Services
  1 New York Plaza
  38th Floor
  New York
  NY
  10004
  100432
  297505.97
  702493754
  05/22/2024
  Nasdaq
  American Depositary Shares Representing Ordinary Shares
  05/22/2024
  Share Option Exercise
  Issuer
  N
  50350
  05/22/2024
  Cash
  American Depositary Shares Representing Ordinary Shares
  05/22/2024
  Share Option Exercise
  Issuer
  N
  50082
  05/22/2024
  Cash
  Y
  The number of shares to be sold is in the form of American Depositary Shares ("ADSs"). The number of shares outstanding is in the form of ordinary shares.
  
  Each ADS represents 5 ordinary shares, nominal value GBP 0.003 per ordinary share, of the Issuer.
  05/23/2024
  /s/ Alexandra Hughes-Wilson