Atwood Oceanics (ATW) 10-K 2009 FY Annual report

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 Annual Report of Atwood Oceanics, Inc. (the “Company”) on Form 10-K for the period ended September 30, 2009, 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. §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 as of, and for the periods presented.

Date:           November 25, 2009                                                                           /S/ JOHN R. IRWIN

  John R. Irwin

President and Chief Executive Officer