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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>0001140361-09-028653.txt : 20091209
<SEC-HEADER>0001140361-09-028653.hdr.sgml : 20091209
<ACCEPTANCE-DATETIME>20091209164015
ACCESSION NUMBER:		0001140361-09-028653
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091207
FILED AS OF DATE:		20091209
DATE AS OF CHANGE:		20091209

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMERICAN ITALIAN PASTA CO
		CENTRAL INDEX KEY:			0000849667
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS FOOD PREPARATIONS & KINDRED PRODUCTS [2090]
		IRS NUMBER:				841032638
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		4100 N MULBERRY DRIVE SUITE 200
		CITY:			KANSAS CITY
		STATE:			MO
		ZIP:			64116
		BUSINESS PHONE:		8165026000

	MAIL ADDRESS:	
		STREET 1:		4100 N MULBERRY DRIVE SUITE 200
		CITY:			KANSS CITY
		STATE:			MO
		ZIP:			64116

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GEIST PAUL R
		CENTRAL INDEX KEY:			0001184804

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13403
		FILM NUMBER:		091231322

	MAIL ADDRESS:	
		STREET 1:		4100 N. MULBERRY DRIVE, SUITE 200
		CITY:			KANSAS CITY
		STATE:			MO
		ZIP:			64116
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-12-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000849667</issuerCik>
        <issuerName>AMERICAN ITALIAN PASTA CO</issuerName>
        <issuerTradingSymbol>AIPC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184804</rptOwnerCik>
            <rptOwnerName>GEIST PAUL R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4100 N. MULBERRY DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>KANSAS CITY</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>64116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP &amp; Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock, par value $.001 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2009-12-07</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>494</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>32.91</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30880</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Paul R. Geist by Robert Schuller as Attorney-in-Fact</signatureName>
        <signatureDate>2009-12-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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