The 1944-1945 Toronto Maple Leafs season was the Toronto-based franchise's twenty-eighth season in the National Hockey League, and eighteenth as the Maple Leafs. The Maple Leafs had a mediocre regular season, barely finishing above the .500 mark in wins with 24. Finishing third out of six, the Maple Leafs struggled to maintain any momentum during the season. However, after entering the Stanley Cup playoffs, the Maple Leafs began a streak of surprisingly solid play, eventually winning the NHL championship and the Stanley Cup with it.
Toronto maintained a very inconsistent string of play during the 1944-1945 season, as they began the season by winning their first six games, and 10 of their first 14, before suffering a drop in play where they went 5-10-2 in their next 17 games. The Maple Leafs would continue to be an inconsistent club for the remainder of the year, which included a five game winning streak, and a seven game winless streak. Overall, the Maple Leafs managed to end the season with a 24–22–4 record, earning 52 points, and third place in the NHL standings.
The Maple Leafs offense was led by teenage superstar Ted Kennedy, who turned only 19 during the season, and had a club high 29 goals and 54 points. Gus Bodnar, who was also 19 years old, led the club with 36 assists, while Lorne Carr scored 21 goals and added 25 assists for 46 points. Sweeney Schriner, who only appeared in 26 games, managed to score 22 goals and 37 points. Babe Pratt led the Leafs defence, scoring 18 goals and 41 points, while fellow defenceman Reg Hamilton had 15 points, and a team-high 41 penalty minutes.
In goal, rookie Frank McCool played all 50 games for the Maple Leafs, winning 24 and posting a 3.22 goals against average, while earning 4 shutouts. McCool would win the Calder Memorial Trophy for his efforts.
The Maple Leafs would open the playoffs against the heavily favoured and defending Stanley Cup champions, the Montreal Canadiens, in a best of 7 series. The Canadiens dominated the league, as they had a record of 38–8–4, recording 80 points, 28 more than the Leafs earned in the season. Toronto stunned the Canadiens in the series opener at the Montreal Forum, as Frank McCool shut out the Habs in a 1–0 Maple Leafs victory. The Leafs then went up 2–0 in the series, winning a close game by a 3–2 score. The series shifted to Maple Leaf Gardens, where the Canadiens roared back, easily defeating Toronto 4–1 to cut the Maple Leafs series lead to 2–1. The fourth game was decided in overtime, and it was the Leafs who were victorious, winning 4–3, and taking a commanding 3–1 series lead. The series moved back to Montreal for the fifth game, and the Canadiens easily dismantled the Leafs, winning 10–3, and sending the series back to Toronto for the sixth game. The Maple Leafs would complete the upset, hanging on for a 4–3 win in the game, to win the series 4–2.
Toronto's opponent in the 1945 Stanley Cup Finals was the Detroit Red Wings, who finished the regular season with a 31–14–5 record, earning 67 points, which was 15 higher than the Maple Leafs. The Red Wings had defeated the Boston Bruins in seven games in the first round. Toronto, led by Frank McCool, would shutout the Red Wings in the first two games held at the Detroit Olympia, for an early series lead. The Maple Leafs returned home for the third game, and took a 3–0 series lead, as McCool would earn another shutout as Toronto won the game 1–0. The Red Wings managed to finally break McCool's shutout streak in the fourth game, winning 5–3 to avoid the sweep. Detroit goaltender Harry Lumley then shutout the Leafs in the fifth game by a score of 2–0. Lumley would once again earn a shutout in the sixth game, as Detroit won the game 1–0 in overtime to set up a seventh and deciding game. Toronto, led by goaltender Frank McCool and Babe Pratt, who scored the series winning goal, managed to hang on for a 2–1 victory in the seventh game to win the Stanley Cup for the fifth time in club history, and their first title in three years.