EXHIBIT 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the Registration Statements on Form S-8 (Nos. 333-64584, 333-81802, 333-97857, 333-105872, 333-120270, 333-136997, 333-142837, 333-145287, 333-176003, 333-176004, 333-197751, 333-208966 and 333-216411) of MB Financial, Inc. of our reports dated March 1, 2019, relating to the consolidated financial statements and the effectiveness of internal control over financial reporting of MB Financial, Inc., appearing in this Annual Report on Form 10-K of MB Financial, Inc. and Subsidiaries for the year ended December 31, 2018.

/s/ RSM US LLP

Chicago, Illinois

March 1, 2019