<SUBMISSION>
<ACCESSION-NUMBER>0000893538-05-000027
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20050303
<FILING-DATE>20050304
<DATE-OF-FILING-DATE-CHANGE>20050304
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>ST MARY LAND & EXPLORATION CO
<CIK>0000893538
<ASSIGNED-SIC>1311
<IRS-NUMBER>410518430
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>1776 LINCOLN ST STE 700
<CITY>DENVER
<STATE>CO
<ZIP>80203
<PHONE>303-861-8140
</BUSINESS-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>WILLSON KEVIN E
<CIK>0001277437
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-31539
<FILM-NUMBER>05660498
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>C/O ST MARY LAND & EXPLORATION
<STREET2>580 WESTLAKE PARK BLVD #600
<CITY>HOUSTON
<STATE>TX
<ZIP>77079
<PHONE>9184887600
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>C/O ST MARY LAND & EXPLORATION
<STREET2>7060 S. YALE #800
<CITY>TULSA
<STATE>OK
<ZIP>74136
</MAIL-ADDRESS>
<FORMER-NAME>
<FORMER-CONFORMED-NAME>WILSON KEVIN E
<DATE-CHANGED>20040126
</FORMER-NAME>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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    <ownerSignature>
        <signatureName>Brenda L. Schohn (Attorney-In-Fact)</signatureName>
        <signatureDate>2005-03-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
