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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      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001073329</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001113232</issuerCik>
        <issuerName>AXCELIS TECHNOLOGIES INC</issuerName>
        <secFileNumber>000-30941</secFileNumber>
        <issuerAddress>
          <com:street1>108 CHERRY HILL DRIVE</com:street1>
          <com:city>BEVERLY</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>01915</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>978-787-4000</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>KEITHLEY JOSEPH P</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>control person</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>245 summer street</com:street1>
            <com:city>Boston</com:city>
            <com:stateOrCountry>MA</com:stateOrCountry>
            <com:zipCode>02110</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>3157</noOfUnitsSold>
        <aggregateMarketValue>358224.79</aggregateMarketValue>
        <noOfUnitsOutstanding>32532498</noOfUnitsOutstanding>
        <approxSaleDate>05/30/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>common</securitiesClassTitle>
        <acquiredDate>05/16/2023</acquiredDate>
        <natureOfAcquisitionTransaction>stock award</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Joseph P Keithley</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1875</amountOfSecuritiesAcquired>
        <paymentDate>05/16/2023</paymentDate>
        <natureOfPayment>n/a</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>common</securitiesClassTitle>
        <acquiredDate>05/15/2024</acquiredDate>
        <natureOfAcquisitionTransaction>stock award</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Joseph P Keithley</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1282</amountOfSecuritiesAcquired>
        <paymentDate>05/15/2024</paymentDate>
        <natureOfPayment>n/a</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <remarks>shares are being sold from Joseph P Keithley 1985 Trust U/A 11/8/10</remarks>
      <noticeSignature>
        <noticeDate>05/30/2024</noticeDate>
        <signature>/s/ Audrey Skillern as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Joseph P Keithley</signature>
      </noticeSignature>
    </formData>
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text: 144
  0001073329
  XXXXXXXX
  LIVE
  0001113232
  AXCELIS TECHNOLOGIES INC
  000-30941
  108 CHERRY HILL DRIVE
  BEVERLY
  MA
  01915
  978-787-4000
  KEITHLEY JOSEPH P
  control person
  Common
  Fidelity Brokerage Services LLC
  245 summer street
  Boston
  MA
  02110
  3157
  358224.79
  32532498
  05/30/2024
  NASDAQ
  common
  05/16/2023
  stock award
  Joseph P Keithley
  N
  1875
  05/16/2023
  n/a
  common
  05/15/2024
  stock award
  Joseph P Keithley
  N
  1282
  05/15/2024
  n/a
  Y
  shares are being sold from Joseph P Keithley 1985 Trust U/A 11/8/10
  05/30/2024
  /s/ Audrey Skillern as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Joseph P Keithley