content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
    <!-- Generated by Workiva -->
    <headerData>
      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001256541</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0000861884</issuerCik>
        <issuerName>Reliance Steel &amp; Aluminum Co</issuerName>
        <secFileNumber>001-13122</secFileNumber>
        <issuerAddress>
          <com:street1>16100 N. 71st Street</com:street1>
          <com:street2>Suite 400</com:street2>
          <com:city>Scottsdale</com:city>
          <com:stateOrCountry>AZ</com:stateOrCountry>
          <com:zipCode>85254</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>480-564-5700</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Karla Lewis</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Director / President / CEO</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>JP 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>32000</noOfUnitsSold>
        <aggregateMarketValue>9103360</aggregateMarketValue>
        <noOfUnitsOutstanding>58557052</noOfUnitsOutstanding>
        <approxSaleDate>08/31/2023</approxSaleDate>
        <securitiesExchangeName>NYSE</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>04/03/2023</acquiredDate>
        <natureOfAcquisitionTransaction>Transfer</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>From Karla Lewis, who acquired the shares from RSU vestings on 02/17/23</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>32000</amountOfSecuritiesAcquired>
        <paymentDate>04/03/2023</paymentDate>
        <natureOfPayment>N/A</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <remarks>The shares filed today will be sold by the Todd E. Lewis and Karla Lewis Trust, Karla Lewis as Trustee</remarks>
      <noticeSignature>
        <noticeDate>08/31/2023</noticeDate>
        <signature>/s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Karla Lewis</signature>
      </noticeSignature>
    </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 3103}]
text: 144
  0001256541
  XXXXXXXX
  LIVE
  0000861884
  Reliance Steel & Aluminum Co
  001-13122
  16100 N. 71st Street
  Suite 400
  Scottsdale
  AZ
  85254
  480-564-5700
  Karla Lewis
  Director / President / CEO
  Common Stock
  JP Morgan Securities LLC
  390 Madison Avenue
  6th Floor
  New York
  NY
  10017
  32000
  9103360
  58557052
  08/31/2023
  NYSE
  Common Stock
  04/03/2023
  Transfer
  From Karla Lewis, who acquired the shares from RSU vestings on 02/17/23
  N
  32000
  04/03/2023
  N/A
  Y
  The shares filed today will be sold by the Todd E. Lewis and Karla Lewis Trust, Karla Lewis as Trustee
  08/31/2023
  /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Karla Lewis