<SUBMISSION>
<ACCESSION-NUMBER>0000914190-04-000343
<TYPE>4/A
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20031128
<FILING-DATE>20041115
<DATE-OF-FILING-DATE-CHANGE>20041115
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>SURMODICS INC
<CIK>0000924717
<ASSIGNED-SIC>6794
<IRS-NUMBER>411356149
<STATE-OF-INCORPORATION>MN
<FISCAL-YEAR-END>0930
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>9924 W 74TH ST
<CITY>EDEN PRAIRIE
<STATE>MN
<ZIP>55344
<PHONE>6128292700
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>9924 WEST 74TH ST
<CITY>EDEN PRAIRIE
<STATE>MN
<ZIP>55344
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>BSI CORP
<DATE-CHANGED>19970506
</FORMER-COMPANY>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>OLSETH DALE R
<CIK>0001077511
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4/A
<ACT>34
<FILE-NUMBER>000-23837
<FILM-NUMBER>041144716
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>9924 WEST 74TH STREET
<CITY>EDEN PRAIRIE
<STATE>MN
<ZIP>55344
<PHONE>6128292700
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>9924 WEST 74TH STREET
<CITY>EDEN PRAIRIE
<STATE>MN
<ZIP>55344
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2003-11-28</periodOfReport>

    <dateOfOriginalSubmission>2003-01-03</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0000924717</issuerCik>
        <issuerName>SURMODICS INC</issuerName>
        <issuerTradingSymbol>SRDX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001077511</rptOwnerCik>
            <rptOwnerName>OLSETH DALE R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9924 WEST 74TH STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EDEN PRAIRIE</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55344</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>(1)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person mistakenly filed a Form 4 on December 3, 2003 reporting an acquisition of 2,500 shares of comon stock held indirectly by grandchildren's trust of which reporting person is not deemed to be a beneficial owner.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Dale R. Olseth</signatureName>
        <signatureDate>2004-11-12</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
