-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 GY0WhkaugMuD+dqQxRDUh49XEw7+D9Ashv65fPAMLaB8nzNhOHsDGKItBb+Uwpx2
 BXBPA/bl6ahNBqfo6nQC9Q==

<SEC-DOCUMENT>0001206774-05-001760.txt : 20051107
<SEC-HEADER>0001206774-05-001760.hdr.sgml : 20051107
<ACCEPTANCE-DATETIME>20051107162237
ACCESSION NUMBER:		0001206774-05-001760
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051103
FILED AS OF DATE:		20051107
DATE AS OF CHANGE:		20051107

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DEMOREST HARRY L
		CENTRAL INDEX KEY:			0001209265

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09887
		FILM NUMBER:		051183631

	MAIL ADDRESS:	
		STREET 1:		OREGON STEEL MILLS INC
		STREET 2:		1000 SW BROADWAY STE 2200
		CITY:			PORTLAND
		STATE:			OR
		ZIP:			97205

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OREGON STEEL MILLS INC
		CENTRAL INDEX KEY:			0000830260
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES  ROLLING MILLS (COKE OVENS) [3312]
		IRS NUMBER:				940506370
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1000 SW BROADWAY
		STREET 2:		STE 2200
		CITY:			PORTLAND
		STATE:			OR
		ZIP:			97205
		BUSINESS PHONE:		5032405788

	MAIL ADDRESS:	
		STREET 1:		PO BOX 5368
		CITY:			PORTLAND
		STATE:			OR
		ZIP:			97228
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>os101200_ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-11-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000830260</issuerCik>
        <issuerName>OREGON STEEL MILLS INC</issuerName>
        <issuerTradingSymbol>OS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001209265</rptOwnerCik>
            <rptOwnerName>DEMOREST HARRY L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1000 SW BROADWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 2200</rptOwnerStreet2>
            <rptOwnerCity>PORTLAND</rptOwnerCity>
            <rptOwnerState>OR</rptOwnerState>
            <rptOwnerZipCode>97205-3996</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-11-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>26000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>/s/ Jeff S. Stewart Attorney-in-Fact</signatureName>
        <signatureDate>2005-11-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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