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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Gav/FYRJvZ4Mx7Ar53RkN8ZGIQeZisex2udii+dsZpDxeqGgWPO7b4ruZWsmGlF5
 DRgsZqmq1e9cV31M5tDK9A==

<SEC-DOCUMENT>0001140361-10-010608.txt : 20100308
<SEC-HEADER>0001140361-10-010608.hdr.sgml : 20100308
<ACCEPTANCE-DATETIME>20100308160856
ACCESSION NUMBER:		0001140361-10-010608
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100101
FILED AS OF DATE:		20100308
DATE AS OF CHANGE:		20100308

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KOCH C JAMES
		CENTRAL INDEX KEY:			0001008079

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14092
		FILM NUMBER:		10663897

	MAIL ADDRESS:	
		STREET 1:		C/O THE BOSTON BEER COMPANY
		STREET 2:		75 ARLINGTON ST
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BOSTON BEER CO INC
		CENTRAL INDEX KEY:			0000949870
		STANDARD INDUSTRIAL CLASSIFICATION:	MALT BEVERAGES [2082]
		IRS NUMBER:				043284048
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1226

	BUSINESS ADDRESS:	
		STREET 1:		ONE DESIGN CENTER PLACE
		STREET 2:		SUITE 850
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210
		BUSINESS PHONE:		617-368-5061

	MAIL ADDRESS:	
		STREET 1:		ONE DESIGN CENTER PLACE
		STREET 2:		SUITE 850
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02210
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-01-01</periodOfReport>

    <dateOfOriginalSubmission>2010-01-05</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000949870</issuerCik>
        <issuerName>BOSTON BEER CO INC</issuerName>
        <issuerTradingSymbol>SAM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001008079</rptOwnerCik>
            <rptOwnerName>KOCH C JAMES</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE BOSTON BEER COMPANY</rptOwnerStreet1>
            <rptOwnerStreet2>ONE DESIGN CENTER PLACE, SUITE 850</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02210</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common</value>
            </securityTitle>
            <transactionDate>
                <value>2010-01-01</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>298</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.684</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>388680</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The original filing is being amended to correct the amount reported in column 5, which was incorrectly reported due to administrative error.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Kathleen H. Wade under POA for the benefit ofC. James Koch</signatureName>
        <signatureDate>2010-03-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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