FIRST INTERSTATE BANCSYSTEM INC — Director's Dealing 2010

May 11, 2010

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: FIRST INTERSTATE BANCSYSTEM INC (N/A)
CIK: 0000860413
Period of Report: 2010-05-07

Reporting Person: HEYNEMAN JOHN M JR (Director)

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Options	$15.91	2020-05-07	Class A Common Stock (1972)		Direct
Class B Common Stock	$0.00	2010-05-07	Class A Common Stock (15000)		Direct
Class B Common Stock	$0.00	2010-05-07	Class A Common Stock (123184)		Indirect
Class B Common Stock	$0.00	2010-05-07	Class A Common Stock (3232)		Indirect
Class B Common Stock	$0.00	2010-05-07	Class A Common Stock (1155792)		Indirect

Footnotes

F1: Stock options granted at the discretion of the Compensation Committee of the Board of Directors for no consideration. 100% vested on date of grant.

F2: Class B common stock is convertible into Class A common stock on a share per share basis at any time.

F3: Class B common shares are convertible into Class A common shares at any time, without expiration.

F4: Disclaims beneficial ownership except to the extend of Mr. Heyneman's pecuniary interest in the partnership.