Marie Greyhounds won the J. Ross Robertson Cup, defeating the Oshawa Generals.
On December 11, 1989, the Detroit Compuware Ambassadors were approved to join the league for the 1990–91 season as an expansion team.
The club was owned by former Windsor Compuware Spitfires owner Peter Karmanos.
The club was the first American based team in the OHL, and would play in the city of Detroit.
Note: GP = Games played; W = Wins; L = Losses; T = Ties; GF = Goals for; GA = Goals against; PTS = Points; x = clinched playoff berth; y = clinched division title