<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-03-25</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001072688</issuerCik>
        <issuerName>WESTERN SIERRA BANCORP</issuerName>
        <issuerTradingSymbol>wsba</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001234965</rptOwnerCik>
            <rptOwnerName>WOOD PHILIP S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>WESTERN SIERRA BANCORP</rptOwnerStreet1>
            <rptOwnerStreet2>4080 PLAZA GOLDORADO CIR</rptOwnerStreet2>
            <rptOwnerCity>CAMERON PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95682</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CAO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>phillip wood</signatureName>
        <signatureDate>2004-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>

