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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001127602-11-001371.txt : 20110110
<SEC-HEADER>0001127602-11-001371.hdr.sgml : 20110110
<ACCEPTANCE-DATETIME>20110110184920
ACCESSION NUMBER:		0001127602-11-001371
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110107
FILED AS OF DATE:		20110110
DATE AS OF CHANGE:		20110110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kost Kurt D
		CENTRAL INDEX KEY:			0001345315

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32331
		FILM NUMBER:		11521197

	MAIL ADDRESS:	
		STREET 1:		ONE ALPHA PLACE
		STREET 2:		P. O. BOX 2345
		CITY:			ABINGDON
		STATE:			VA
		ZIP:			24212

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Alpha Natural Resources, Inc.
		CENTRAL INDEX KEY:			0001301063
		STANDARD INDUSTRIAL CLASSIFICATION:	BITUMINOUS COAL & LIGNITE SURFACE MINING [1221]
		IRS NUMBER:				421638663
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE ALPHA PLACE
		STREET 2:		P.O. BOX 2345
		CITY:			ABINGDON
		STATE:			VA
		ZIP:			24212
		BUSINESS PHONE:		276-619-4410

	MAIL ADDRESS:	
		STREET 1:		ONE ALPHA PLACE
		STREET 2:		P.O. BOX 2345
		CITY:			ABINGDON
		STATE:			VA
		ZIP:			24212

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Foundation Coal Holdings, Inc.
		DATE OF NAME CHANGE:	20040819
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-01-07</periodOfReport>

    <issuer>
        <issuerCik>0001301063</issuerCik>
        <issuerName>Alpha Natural Resources, Inc.</issuerName>
        <issuerTradingSymbol>ANR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001345315</rptOwnerCik>
            <rptOwnerName>Kost Kurt D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE ALPHA PLACE</rptOwnerStreet1>
            <rptOwnerStreet2>P. O. BOX 2345</rptOwnerStreet2>
            <rptOwnerCity>ABINGDON</rptOwnerCity>
            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>24212</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-01-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>12666</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>141425</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-01-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1576</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>139849</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock unit award granted to reporting person under the Issuer's 2010 Long-Term Incentive Plan.  The restricted stock units vest in three equal annual installments beginning January 7, 2012.</footnote>
        <footnote id="F2">Represents shares tendered by reporting person to the Issuer for payment of withholding taxes on restricted stock units vesting on even date; this transaction is exempt pursuant to Rule 16b-3 under the Securities and Exchange Act of 1934.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Edythe C. Katz, Attorney-in-Fact</signatureName>
        <signatureDate>2011-01-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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