-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 L36lV1wDIuT0CD2/jNA+PSt1Ntfj9zjfFA8ueGYmVhdQCr9LstF+hZMNPT6z8pSa
 IHa71/mrsvlIowmbs02feQ==

<SEC-DOCUMENT>0001209191-05-025441.txt : 20050512
<SEC-HEADER>0001209191-05-025441.hdr.sgml : 20050512
<ACCEPTANCE-DATETIME>20050512080331
ACCESSION NUMBER:		0001209191-05-025441
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050412
FILED AS OF DATE:		20050512
DATE AS OF CHANGE:		20050512

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ENGELHARDT IRL F
		CENTRAL INDEX KEY:			0001213883

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16463
		FILM NUMBER:		05822404

	BUSINESS ADDRESS:	
		STREET 1:		PEABODY ENERGY CORP
		STREET 2:		701 MARKET ST
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63101

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PEABODY ENERGY CORP
		CENTRAL INDEX KEY:			0001064728
		STANDARD INDUSTRIAL CLASSIFICATION:	BITUMINOUS COAL & LIGNITE SURFACE MINING [1221]
		IRS NUMBER:				134004153
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		701 MARKET ST
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63101-1826
		BUSINESS PHONE:		3143423400

	MAIL ADDRESS:	
		STREET 1:		701 MARKET ST
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63101-1826

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	P&L COAL HOLDINGS CORP
		DATE OF NAME CHANGE:	19980623
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc4a.xml
<DESCRIPTION>FORM 4/A SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2005-04-12</periodOfReport>

    <dateOfOriginalSubmission>2005-04-14</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001064728</issuerCik>
        <issuerName>PEABODY ENERGY CORP</issuerName>
        <issuerTradingSymbol>BTU</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001213883</rptOwnerCik>
            <rptOwnerName>ENGELHARDT IRL F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>701 MARKET STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST. LOUIS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63101-1826</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-12</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>51586</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>45.018</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>297118</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The sale reported in this Form 4 was effected pursuant to a pre-existing Rule 10b5-1 trading plan adopted by the reporting person.</footnote>
        <footnote id="F2">Does not include 15,626 shares held directly (including 2,166 shares acquired under the Company's Employee Stock Purchase Plan), 8,358 shares held indirectly by the Company's 401(k) plan, and 2,200 shares held indirectly by Mr. Engelhardt's spouse.  Amounts have been adjusted to reflect the 2-for-1 stock split announced by the Company in March 2005.</footnote>
        <footnote id="F3">This report is being filed to correct the amount of securities beneficially owned by the reporting person following the reported transaction.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Irl F. Engelhardt


by Joseph W. Bean, Attorney-in-Fact</signatureName>
        <signatureDate>2005-05-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----