<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType><periodOfReport>2003-11-07</periodOfReport>
    <issuer>
        <issuerCik>0000873603</issuerCik>
        <issuerName>EXCEL TECHNOLOGY INC</issuerName>
        <issuerTradingSymbol>XLTC</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001234572</rptOwnerCik>
            <rptOwnerName>BRESLOW HOWARD S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>BRESLOW &amp; WALKER, LLP</rptOwnerStreet1>
            <rptOwnerStreet2>100 JERICHO QUADRANGLE</rptOwnerStreet2>
            <rptOwnerCity>JERICHO</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11753</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
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Breslow</signatureName><signatureDate>2003-11-10</signatureDate></ownerSignature></ownershipDocument>

