EXHIBIT 32.1


                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
                       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 Atwood Oceanics, Inc. (the "Company")
on Form 10-Q for the period ended June 30, 2007, as filed with the Securities
and Exchange Commission on the date hereof (the "Report"), I, John R. Irwin,
Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. ss.1350,
as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to
the best of my knowledge:

        (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 for the periods presented.



Date:    August 8, 2007                   /s/ JOHN R. IRWIN
                                          John R. Irwin
                                          President and Chief Executive Officer