The Terps can clinch a spot in the Big Ten tournament with a win Saturday.
The Terps allowed four runs in the ninth, but AJ Lee's walk-off home run ended it.
The Terps will need to find success against Iowa and get help from around the conference.
The Terps will take on Iowa next in their final Big Ten series of the regular season.
The Terps have dropped five of their last six contests.
With the Big Ten tournament looming, the Terps are clinging to their eighth-place conference ranking.
The Wolverines racked up 13 runs on 11 hits.
A five-run seventh inning pushed the Wolverines too far in front.
Tyler Blohm struck out six batters and the Terps allowed one hit.
After taking the first game Saturday, Maryland struggled on the mound in game two.