The 2004 Toronto Argonauts season was the 115th season for the team since the franchise's inception in 1873. The team finished in second place in the East Division with a 10–7–1 record and qualified for the playoffs for the third consecutive year. The Argonauts defeated the Hamilton Tiger-Cats in the East Semi-Final and then won the Eastern Final against the Montreal Alouettes. Toronto faced the BC Lions in the 92nd Grey Cup and won their 15th Grey Cup championship by a score of 27-19.