1 EXHIBIT 23.1 CONSENT OF INDEPENDENT AUDITORS We consent to the reference to our firm under the caption "Experts" and to the use of our report related to Mutual Savings Bank dated March 7, 2000 and our report related to First Northern Capital Corp. dated January 22, 1999 included and incorporated by reference, respectively, in the Registration Statement (Form S-4) of Bank Mutual Corporation for the registration of up to 8,996,198 shares of its common stock. /s/ Ernst & Young LLP Milwaukee, Wisconsin August 28, 2000 1 of 1