Exhibit 32.01 I, Robert D. Walter, Chairman and Chief Executive Officer, of Cardinal Health, Inc. (the "Company"), certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that: (1) the Quarterly report on Form 10-Q for the fiscal quarter ended December 31, 2003, (the "Periodic Report") containing the financial statements of the Company, which this statement accompanies, fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m), and (2) the information contained in the Periodic Report fairly presents, in all material respects, the financial condition and results of operations of the Company. Dated: February 17, 2004 /s/ Robert D. Walter ------------------------- Robert D. Walter Chairman, and Chief Executive Officer