EXHIBIT 32.2


                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


         In connection with the quarterly report of Willbros Group, Inc. (the
"Company") on Form 10-Q for the quarter ended June 30, 2005 as filed with the
Securities and Exchange Commission on the date hereof (the "Report"), I, Warren
L. Williams, Chief Financial Officer of the Company, hereby certify pursuant to
18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley
Act of 2002, that:

         1.       The Report fully complies with the requirements of Section
                  13(a) or 15(d) of the Securities Exchange Act of 1934; and

         2.       The information contained in the Report fairly presents, in
                  all material respects, the financial condition and results of
                  operations of the Company.

Date: November 21, 2005                     /s/ Warren L. Williams
                                            ------------------------------------
                                            Warren L. Williams
                                            Chief Financial Officer



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