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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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MIC-Info: RSA-MD5,RSA,
 K/gTek5dOOO/iH8y4QLTdEmpflyQXQoXejGGzQVMRsEjBilt/OtdmMmBcKBJngoJ
 O6VS+xCZQsub5jf6ejux6w==

<SEC-DOCUMENT>0001042167-10-000097.txt : 20100326
<SEC-HEADER>0001042167-10-000097.hdr.sgml : 20100326
<ACCEPTANCE-DATETIME>20100326104347
ACCESSION NUMBER:		0001042167-10-000097
CONFORMED SUBMISSION TYPE:	D
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		Rule 506
FILED AS OF DATE:		20100326
DATE AS OF CHANGE:		20100326
EFFECTIVENESS DATE:		20100326

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Prestress Engineering Co LLC
		CENTRAL INDEX KEY:			0001487972
		IRS NUMBER:				800480415
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		D
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-139975
		FILM NUMBER:		10706476

	BUSINESS ADDRESS:	
		STREET 1:		2220 IL ROUTE 176
		CITY:			CRYSTAL LAKE
		STATE:			IL
		ZIP:			60014
		BUSINESS PHONE:		815-459-4545

	MAIL ADDRESS:	
		STREET 1:		2220 IL ROUTE 176
		CITY:			CRYSTAL LAKE
		STATE:			IL
		ZIP:			60014
</SEC-HEADER>
<DOCUMENT>
<TYPE>D
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0603</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001487972</cik>
        <entityName>Prestress Engineering Co LLC</entityName>
        <issuerAddress>
            <street1>2220 IL ROUTE 176</street1>
            <city>CRYSTAL LAKE</city>
            <stateOrCountry>IL</stateOrCountry>
            <zipCode>60014</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>815-459-4545</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <previousName>PECM LLC</previousName>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Liability Company</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2009</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Christian</firstName>
                <middleName>R.</middleName>
                <lastName>Newkirk</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2220 IL Route 176</street1>
                <city>Crystal Lake</city>
                <stateOrCountry>IL</stateOrCountry>
                <zipCode>60014</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Charles</firstName>
                <middleName>J.</middleName>
                <lastName>Tasch</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2220 IL Route 176</street1>
                <city>Crystal Lake</city>
                <stateOrCountry>IL</stateOrCountry>
                <zipCode>60014</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Michael</firstName>
                <middleName>S.</middleName>
                <lastName>Felvey</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2220 IL Route 176</street1>
                <city>Crystal Lake</city>
                <stateOrCountry>IL</stateOrCountry>
                <zipCode>60014</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>M.</firstName>
                <middleName>Brantley</middleName>
                <lastName>Barrow</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2220 IL Route 176</street1>
                <city>Crystal Lake</city>
                <stateOrCountry>IL</stateOrCountry>
                <zipCode>60014</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>L.L.C.</firstName>
                <lastName>CM Acquisitions,</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>230 West Monroe Street</street1>
                <street2>Suite 2000</street2>
                <city>Chicago</city>
                <stateOrCountry>IL</stateOrCountry>
                <zipCode>60606</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Managing Member</relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Manufacturing</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2010-03-11</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>true</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>25000</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>11900000</totalOfferingAmount>
            <totalAmountSold>11900000</totalAmountSold>
            <totalRemaining>0</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>36</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Prestress Engineering Co LLC</issuerName>
                <signatureName>/s/ Michael Felvey</signatureName>
                <nameOfSigner>CM Acquisitions, L.L.C. BY Michael Felvey</nameOfSigner>
                <signatureTitle>Principal of Managing Member</signatureTitle>
                <signatureDate>2010-03-26</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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