The 1988–89 OHL season was the ninth season of the Ontario Hockey League. The Hamilton Steelhawks move to Niagara Falls becoming the Niagara Falls Thunder. The Kingston Canadians rename themselves to the Kingston Raiders. The OHL awards the inaugural Bill Long Award for distinguished service to the OHL. Fifteen teams each played 66 games. The Peterborough Petes won the J. Ross Robertson Cup, defeating the Niagara Falls Thunder.