Exhibit 32.1 KERR-McGEE CORPORATION Kerr-McGee Center Oklahoma City, Oklahoma 73125 CERTIFICATION OF CHIEF EXECUTIVE OFFICER REGARDING PERIODIC REPORT CONTAINING FINANCIAL STATEMENTS I, Luke R. Corbett, the Chief Executive Officer of Kerr-McGee Corporation (the "Issuer"), in compliance with 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, hereby certify in connection with the Issuer's Quarterly Report on Form 10-Q for the period that ended September 30, 2003 as filed with the Securities and Exchange Commission (the "Report") that: o the Report fully complies with the requirements of Section 13(a) of the Securities Exchange Act of 1934; and o information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Issuer. /s/ Luke R. Corbett - ---------------------- Luke R. Corbett Chief Executive Officer November 11, 2003 Exhibit 32.2 KERR-McGEE CORPORATION Kerr-McGee Center Oklahoma City, Oklahoma 73125 CERTIFICATION OF CHIEF FINANCIAL OFFICER REGARDING PERIODIC REPORT CONTAINING FINANCIAL STATEMENTS I, Robert M. Wohleber, the Chief Financial Officer of Kerr-McGee Corporation (the "Issuer"), in compliance with 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, hereby certify in connection with the Issuer's Quarterly Report on Form 10-Q for the period that ended September 30, 2003 as filed with the Securities and Exchange Commission (the "Report") that: o the Report fully complies with the requirements of Section 13(a) of the Securities Exchange Act of 1934; and o information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Issuer. /s/ Robert M. Wohleber - ---------------------- Robert M. Wohleber Chief Financial Officer November 11, 2003