The 1976–77 OMJHL season was the third season of the Ontario Major Junior Hockey League. Twelve teams each played 66 games. The Ottawa 67's won the J. Ross Robertson Cup, defeating the London Knights.
The St. Catharines Black Hawks moved to Niagara Falls, Ontario, becoming the Flyers. Their owner Hap Emms using the name of his former team. The Hamilton Fincups then moved to the vacant Jack Gatecliff Arena in St. Catharines, Ontario after the ice-making machine at the ancient Hamilton Forum broke down irreparably a month before the season began.
Sault Ste. Marie Greyhounds defeat Peterborough Petes 3–1
Windsor Spitfires defeat Kitchener Rangers 3–0
Ottawa 67's defeat Sault Ste. Marie Greyhounds 4–0, 1 tie
Kingston Canadians defeat Sudbury Wolves 4–1, 1 tie
St. Catharines Fincups defeat Windsor Spitfires 4–2
London Knights defeat Toronto Marlboros 4–1, 1 tie