Jarryd Cole scored 13 points and grabbed nine rebounds for Iowa (9-13, 2-8 Big-10), while Bryce Cartwright played distributor, to the tune of 12 points and 10 assists. Eric May added 11 points on 4-of-5 shooting.
Michigan State fell behind early and never fully recovered, shooting just 24.1 percent in the first half to trail 41-20 at the break.
Iowa drained 9-of-11 second half free throws to seal the win.
The Hawkeyes held the Spartans to just 33.9 percent shooting on the night, including 22.2 percent from downtown.