EXHIBIT 23

            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the following documents of our
report dated May 14, 2004 with respect to the consolidated financial statements
of Anchor BanCorp Wisconsin Inc. included in the Annual Report (Form 10-K) for
the year ended March 31, 2004.

      -     Registration Statement (Form S-8 No. 33-52666) pertaining to the
            1992 Stock Incentive Plan.

      -     Registration Statement (Form S-8 No. 333-81959) pertaining to the
            1999 Employee Stock Purchase Plan.

      -     Registration Statement (Form S-8 No. 333-81609) pertaining to the
            FCB Financial Corp. 1998 Incentive Plan, FCB Financial Corp. 1993
            Stock Option and Incentive Plan, OSB Financial Corp 1992 Stock
            Option and Incentive Plan.

      -     Registration Statement (Form S-8 No. 33-46536) pertaining to the
            AnchorBank, fsb Retirement Plan.

/s/ Ernst & Young LLP
Milwaukee, Wisconsin
June 7, 2004

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