-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 B8r0SK7nuKQ+DuTUJHoNOY6YInBvLU6QZD5ExHz8LL2TLoSdYduevXY3aatC1wpf
 Z081c7cxZpQD0/rTN1Cn7g==

<SEC-DOCUMENT>0001140361-10-038066.txt : 20100921
<SEC-HEADER>0001140361-10-038066.hdr.sgml : 20100921
<ACCEPTANCE-DATETIME>20100921151144
ACCESSION NUMBER:		0001140361-10-038066
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100920
FILED AS OF DATE:		20100921
DATE AS OF CHANGE:		20100921

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HENRY CHARLES W
		CENTRAL INDEX KEY:			0001193778

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-00599
		FILM NUMBER:		101082524

	MAIL ADDRESS:	
		STREET 1:		62 TUNXIS VILLAGE
		CITY:			FARMINGTON
		STATE:			CT
		ZIP:			06032

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EASTERN CO
		CENTRAL INDEX KEY:			0000031107
		STANDARD INDUSTRIAL CLASSIFICATION:	CUTLERY, HANDTOOLS & GENERAL HARDWARE [3420]
		IRS NUMBER:				060330020
		STATE OF INCORPORATION:			CT
		FISCAL YEAR END:			0102

	BUSINESS ADDRESS:	
		STREET 1:		112 BRIDGE ST
		STREET 2:		P O BOX 460
		CITY:			NAUGATUCK
		STATE:			CT
		ZIP:			06770
		BUSINESS PHONE:		2037292255

	MAIL ADDRESS:	
		STREET 1:		112 BRIDGE STREET
		STREET 2:		P O BOX 460
		CITY:			NAUGATUCK
		STATE:			CT
		ZIP:			06770
</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>2010-09-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000031107</issuerCik>
        <issuerName>EASTERN CO</issuerName>
        <issuerTradingSymbol>EML</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001193778</rptOwnerCik>
            <rptOwnerName>HENRY CHARLES W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>112 BRIDGE STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NAUGATUCK</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06770</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>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2010-09-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>389</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.81</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>77001</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">389 shares acquired under The Eastern Company Director's Fee Program pursuant to Rule 16b-3(d).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Charles W. Henry, by Theresa P. Dews his attorney-in-fact</signatureName>
        <signatureDate>2010-09-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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