<SUBMISSION>
<ACCESSION-NUMBER>0001195948-04-000007
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20041109
<FILING-DATE>20041112
<DATE-OF-FILING-DATE-CHANGE>20041112
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>BUSSE KEITH E
<CIK>0001195948
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-21719
<FILM-NUMBER>041135660
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>6714 POINTE INVERNESS WAY
<CITY>FORT WAYNE
<STATE>IN
<ZIP>46804
</MAIL-ADDRESS>
</REPORTING-OWNER>
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>STEEL DYNAMICS INC
<CIK>0001022671
<ASSIGNED-SIC>3312
<IRS-NUMBER>351929476
<STATE-OF-INCORPORATION>IN
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>6714 POINTE INVERNESS WAY
<STREET2>SUITE 200
<CITY>FORT WAYNE
<STATE>IN
<ZIP>46804
<PHONE>2604593553
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>6714 POINTE INVERNESS WAY
<STREET2>SUITE 200
<CITY>FORT WAYNE
<STATE>IN
<ZIP>46804
</MAIL-ADDRESS>
</ISSUER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">Exercise of stock option and acquisition of underlying stock pursuant to employee stock option plan exempt under Rule 16b-6(b).</footnote>
        <footnote id="F2">Disposition of option exempt under Rule 16b-3(e).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Keith E. Busse</signatureName>
        <signatureDate>2004-11-11</signatureDate>
    </ownerSignature>
</ownershipDocument>

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