Sterling Infrastructure (STRL) 10-Q 2009 Q2 Quarterly report

Exhibit 32.0

CERTIFICATION

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

(Subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code)

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code), each of the undersigned officers of Sterling Construction Company, Inc., a Delaware corporation (the “Company”), does hereby certify that, to his knowledge:

(i)   the Quarterly Report on Form 10-Q for the quarter ended June 30, 2009 (the “Form 10-Q”) of the Company fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(ii)   the information contained in the Form 10-Q fairly represents, in all material respects, the financial condition and results of operations of the Company.

Dated:           August 10, 2009                             /s/ Patrick T. Manning

Patrick T. Manning

Chief Executive Officer

Dated:           August 10, 2009                             /s/ James H. Allen, Jr.

James H. Allen, Jr.

Senior Vice-President and Chief Financial Officer

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