Alex Hesson went to the far post off a set piece from Kristen Elam in the 24th minute to give the Quakers their first goal, then 50 seconds later Erica Sayler nailed in a goal to make the score 2-0.
That would be all the offense Wilmington needed as Maria Larson had four saves in goal.
Kelly Aughinbaugh (Aurora/Aurora) had four shots to pace the Purple Raiders.
Wilmington moves to 9-3-2 overall and 4-1 in the OAC with the win, while Mount Union falls to 3-11-1 overall and 0-5 in the conference after the loss.
The Raiders return home to host Muskingum Wednesday at 4 pm in Mount Union Stadium.