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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 C5HwbXemyp+QOtib4dd1RTxSGrdgMKXxbHWlUuz9NkUYheVT8qaZm4xMD6lDFp/d
 Sc1mFsCoegl3HvoArsXHbQ==

<SEC-DOCUMENT>0001423221-08-000023.txt : 20080630
<SEC-HEADER>0001423221-08-000023.hdr.sgml : 20080630
<ACCEPTANCE-DATETIME>20080630140055
ACCESSION NUMBER:		0001423221-08-000023
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080620
FILED AS OF DATE:		20080630
DATE AS OF CHANGE:		20080630

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Quanex Building Products CORP
		CENTRAL INDEX KEY:			0001423221
		STANDARD INDUSTRIAL CLASSIFICATION:	ROLLING DRAWING & EXTRUDING OF NONFERROUS METALS [3350]
		IRS NUMBER:				261561397
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1031

	BUSINESS ADDRESS:	
		STREET 1:		1900 WEST LOOP SOUTH
		STREET 2:		SUITE 1500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77027
		BUSINESS PHONE:		7139614600

	MAIL ADDRESS:	
		STREET 1:		1900 WEST LOOP SOUTH
		STREET 2:		SUITE 1500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77027

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROSS JOSEPH J
		CENTRAL INDEX KEY:			0001028618

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33913
		FILM NUMBER:		08925112

	BUSINESS ADDRESS:	
		STREET 1:		1415 W 22ND ST
		STREET 2:		STE 1100
		CITY:			OAK BROOK
		STATE:			IL
		ZIP:			60523
		BUSINESS PHONE:		6309542000
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2008-06-20</periodOfReport>

    <dateOfOriginalSubmission>2008-06-24</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0001423221</issuerCik>
        <issuerName>Quanex Building Products CORP</issuerName>
        <issuerTradingSymbol>NX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001028618</rptOwnerCik>
            <rptOwnerName>ROSS JOSEPH J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1900 WEST LOOP SOUTH</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1500</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77027</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-06-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12919</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>16</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19192</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Amended only to include balance footnote to disclose 6,273 shares received as a dividend on Quanex Corporation common stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>John J. Mannion, Power of Attorney</signatureName>
        <signatureDate>2008-06-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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