Exhibit 32.1

Certification by Chief Executive Officer Pursuant to 18 U.S.C. Section 1350,
as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

I, Paul David Miller, Chief Executive Officer of Alliant Techsystems Inc. (the “Company”), certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to my knowledge:

(1)the Quarterly Report on Form 10-Q for the fiscal quarter ended June 29, 2003, as filed with the Securities and Exchange Commission on the date hereof (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 the dates and for the periods expressed in the Report.

Dated: August 12, 2003

/s/ Paul David Miller

Paul David Miller

Chief Executive Officer and Chairman of the Board