Rule 424(b)(2) File No. 333-33814 Pricing Supplement #88 dated September 2nd, 2004 to the Prospectus Dated April 12, 2000 and Prospectus Supplement Dated October 21, 2003 Marshall & Ilsley Corporation MiNotes SM Due from 9 Months to 30 Years Trade Date: August 30, 2004 Issue Price: 100% Original Issue Date: September 2, 2004 Principal Amount: $290,000 Maturity Date: June 16, 2008 Interest Rate: 3.40% Interest Payment Dates: 10/15/04 & Monthly thereafter Purchasing Agent acting as Principal: Merrill Lynch & Co. Purchasing Agent Commission: .625% Proceeds Before expenses: 99.375% ($288,187.50) Survivor's Option: Yes Redemption or Repayment: At Maturity Redemption/Repayment Terms: Not Applicable Minimum Denomination: $1,000 minimum investment with increments of $1,000 CUSIP No.: 57183MDV9 Original Issue Discount: No Notes: All trades settle without accrued interest and clear SDFS: DTC Book-Entry only Merrill Lynch DTC Participant Number: 161 ??