The 1979–80 QMJHL season was the 11th season in the history of the Quebec Major Junior Hockey League. Ten teams played 72 games each in the schedule. The Sherbrooke Castors finished first overall in the regular season, winning the Jean Rougeau Trophy. The Cornwall Royals, led by rookie Dale Hawerchuk won the President's Cup, defeating the Sherbrooke Castors in the finals. Cornwall went on to win the 1980 Memorial Cup, winning their second Memorial Cup championship.