Dispatchers said the fire started in one of the stadium's suites. The first responders called in two other fire departments to help fight the blaze.
All employees reportedly made it out of the stadium safely, but parts of the building have collapsed.
The stadium, which is about five miles north of Grand Rapids, opened in 1994 and seats 10,071.
@FifthThirdBall park on fire. I am here. pic.twitter.com/Jt5OZIlTWG — John Gonzalez (@MichiganGonzo) January 3, 2014