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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001104659-07-090516.txt : 20071221
<SEC-HEADER>0001104659-07-090516.hdr.sgml : 20071221
<ACCEPTANCE-DATETIME>20071221140225
ACCESSION NUMBER:		0001104659-07-090516
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20071218
FILED AS OF DATE:		20071221
DATE AS OF CHANGE:		20071221

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMERICAN DG ENERGY INC
		CENTRAL INDEX KEY:			0001378706
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC, GAS & SANITARY SERVICES [4900]
		IRS NUMBER:				043569304
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		45 FIRST AVENUE
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		781-622-1120

	MAIL ADDRESS:	
		STREET 1:		45 FIRST AVENUE
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Loumidis Anthony S
		CENTRAL INDEX KEY:			0001385156

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-52294
		FILM NUMBER:		071322288

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		781-622-1120

	MAIL ADDRESS:	
		STREET 1:		C/O AMERICAN DG ENERGY INC.
		STREET 2:		45 FIRST AVENUE
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-12-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001378706</issuerCik>
        <issuerName>AMERICAN DG ENERGY INC</issuerName>
        <issuerTradingSymbol>ADGE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001385156</rptOwnerCik>
            <rptOwnerName>Loumidis Anthony S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O AMERICAN DG ENERGY INC.</rptOwnerStreet1>
            <rptOwnerStreet2>45 FIRST AVENUE</rptOwnerStreet2>
            <rptOwnerCity>WALTHAM</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02451</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Options (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.90</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-12-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>250000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2017-12-18</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>250000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>250000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Grant of stock option pursuant to the American DG Energy Inc. 2005 Stock Incentive Plan.  The option vests in ten equal annual installments beginning on December 31, 2007.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Anthony S. Loumidis</signatureName>
        <signatureDate>2007-12-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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