The 1991 Toronto Argonauts season was the 102nd season for the team since the franchise's inception in 1873. The team finished in first place in the East Division with a 13–5–0 record and qualified for the playoffs for the sixth consecutive year. The Argonauts defeated the Winnipeg Blue Bombers in the Eastern Final and qualified for the 79th Grey Cup. Toronto defeated the Calgary Stampeders in a rematch of the 1971 Grey Cup, winning their 12th Grey Cup championship by a score of 36-21.