Rule 424(b)(2) File No. 333-33814 Pricing Supplement #90 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: $615,000 Maturity Date: June 15, 2010 Interest Rate: 4.00% Interest Payment Dates: 10/15/04 & Monthly thereafter Purchasing Agent acting as Principal: Merrill Lynch & Co. Purchasing Agent Commission: 1.00% Proceeds Before expenses: 99.00% ($608,850.00) 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.: 57183MDX5 Original Issue Discount: No Notes: All trades settle without accrued interest and clear SDFS: DTC Book-Entry only Merrill Lynch DTC Participant Number: 161 ??