<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-08-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000855372</issuerCik>
        <issuerName>ECO2 PLASTICS INC</issuerName>
        <issuerTradingSymbol>ECOO.0B</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001437472</rptOwnerCik>
            <rptOwnerName>Moragne John</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O TRIDENT CAPITAL</rptOwnerStreet1>
            <rptOwnerStreet2>505 HAMILTON AVENUE, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>PALO ALTO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94301</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Convertible Secured Promissory Note</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>33333333</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>500000</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-03-31</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33333333</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33333333</value>
                    <footnoteId id="F3"/>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock Purchase Warrant</value>
                <footnoteId id="F7"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.015</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16666667</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F8"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-08-22</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-14</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16666667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16666667</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Convertible Secured Promissory Note</value>
                <footnoteId id="F9"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>33333333</value>
                    <footnoteId id="F10"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>500000</value>
                    <footnoteId id="F10"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-03-31</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                    <footnoteId id="F10"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33333333</value>
                    <footnoteId id="F10"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>66666666</value>
                    <footnoteId id="F5"/>
                    <footnoteId id="F10"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock Purchase Warrant</value>
                <footnoteId id="F11"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.015</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16666667</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F12"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-08-28</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-14</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16666667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33333334</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Convertible Secured Promissory Note</value>
                <footnoteId id="F13"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-09-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>66666667</value>
                    <footnoteId id="F14"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>1000000</value>
                    <footnoteId id="F14"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2009-03-31</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                    <footnoteId id="F14"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>66666667</value>
                    <footnoteId id="F14"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>133333333</value>
                    <footnoteId id="F5"/>
                    <footnoteId id="F14"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Common Stock Purchase Warrant</value>
                <footnoteId id="F15"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.015</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-09-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>33333334</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F16"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2008-09-15</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-14</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33333334</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>66666668</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Convertible Secured Promissory Notes dated 8/22/2008 (the &quot;8/22 Notes&quot;) are held by Trident Capital Fund-VI, L.P. (&quot;Trident Capital&quot;) which holds an 8/22 Note for $481,332.31 and Trident Capital Fund-VI Principals Fund, L.L.C. (&quot;Trident Principals&quot;) which holds an 8/22 Note for $18,667.69.</footnote>
        <footnote id="F2">In the event the Promisor has consummated a new equity financing in a single transaction or a series of related transactions yielding gross proceeds of at least $1,000,000.00 in the aggregate (the &quot;Next Equity Financing&quot;), then the underlying securities shall consist of equity securities issued in such Next Equity Financing, at a price per share equal to the lesser of (x) 80% of the purchase price paid by the purchasers of other securities sold in such Next Equity Financing or (y) $0.015.  If the Next Equity Financing has not occurred, then the Conversion Securities will be convertible at a price per share of $0.015.</footnote>
        <footnote id="F3">The 8/22 Notes represent a principal investment of $500,000.  The title and amount of underlying securities will be dependent upon the conversion requirements set forth in footnote (2) listed above.  As of the date of filing, the conversion price of the Notes is $0.015 and the Notes are convertible into an aggregate of 33,333,333 shares of Series C Convertible Preferred Stock.  Each share of Series C Convertible Preferred Stock is convertible into one share of Common Stock as of the date of filing.</footnote>
        <footnote id="F4">The Convertible Secured Promissory Note has no expiration date.</footnote>
        <footnote id="F5">In addition, Trident Capital Management-VI, LLC, Trident Capital Fund-VI, LP and Trident Capital Fund-VI Principals LLC, of which Mr. Moragne is a managing member, hold 75,160,274 shares of Series B-1 Convertible Preferred Stock.  Trident Capital Management-VI, LLC, Trident Capital Fund-VI, LP and Trident Capital Fund-VI Principals LLC also have the right to hold 120,000,000 shares of Series B-2 Convertible Preferred Stock.</footnote>
        <footnote id="F6">Managing Member of Trident Capital Management-VI, L.L.C.; Managing Member or General Partner of Trident Capital Fund-VI, L.P. and Trident Capital Fund-VI Principals, L.L.C.</footnote>
        <footnote id="F7">The 8/22/08 warrants to purchase Common Stock (the &quot;8/22 Warrants&quot;) are held by Trident Capital which holds warrants to purchase 16,044,411 shares and Trident Principals which holds warrants to purchase 622,256 shares.</footnote>
        <footnote id="F8">The 8/22 Warrants to purchase Common Stock were received in exchange for $500.00, for a price equivalent to $0.00003 per share.</footnote>
        <footnote id="F9">The Convertible Secured Promissory Notes dated 8/28/2008 (the &quot;8/28 Notes&quot;) are held by Trident Capital Fund-VI, L.P. (&quot;Trident Capital&quot;) which holds an 8/28 Note for $481,332.31 and Trident Capital Fund-VI Principals Fund, L.L.C. (&quot;Trident Principals&quot;) which holds an 8/28 Note for $18,667.69.</footnote>
        <footnote id="F10">The 8/28 Notes represent a principal investment of $500,000.  The title and amount of underlying securities will be dependent upon the conversion requirements set forth in footnote (2) listed above.  As of the date of filing, the conversion price of the Notes is $0.015 and the Notes are convertible into an aggregate of 33,333,333 shares of Series C Convertible Preferred Stock. Each share of Series C Convertible Preferred Stock is convertible into one share of Common Stock as of the date of filing.</footnote>
        <footnote id="F11">The 8/28/08 warrants to purchase Common Stock (the &quot;8/28 Warrants&quot;) are held by Trident Capital which holds warrants to purchase 16,044,411 shares and Trident Principals which holds warrants to purchase 622,256 shares.</footnote>
        <footnote id="F12">The 8/28 Warrants to purchase Common Stock were received in exchange for $500.00, for a price equivalent to $0.00003 per share.</footnote>
        <footnote id="F13">The Convertible Secured Promissory Notes dated 9/15/2008 (the &quot;9/15 Notes&quot;) are held by Trident Capital which holds a 9/15 Note for $962,664.62 and Trident Principals which holds a 9/15 Note for $37,335.38.</footnote>
        <footnote id="F14">The 9/15 Notes represent a principal investment of $1,000,000.  The title and amount of underlying securities will be dependent upon the conversion requirements set forth in footnote (2) listed above.  As of the date of filing, the conversion price of the Notes is $0.015 and the Notes are convertible into an aggregate of 66,666,666 shares of Series C Convertible Preferred Stock. As of the date of this filing, each share of Series C Convertible Preferred Stock, when created, is convertible into one share of Common Stock.</footnote>
        <footnote id="F15">The 9/15 warrants to purchase Common Stock (the &quot;9/15 Warrants&quot;) are held by Trident Capital Fund-VI, L.P. (&quot;Trident Capital&quot;) which holds warrants to purchase 32,088,821 shares and Trident Capital Fund-VI Principals Fund, L.L.C. (&quot;Trident Principals&quot;) which holds warrants to purchase 1,244,513 shares.</footnote>
        <footnote id="F16">The 9/15 Warrants to purchase Common Stock were received in exchange for $1000.00, for a price equivalent to $0.00003 per share.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>John Moragne</signatureName>
        <signatureDate>2008-10-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
