Canadian football is a form of gridiron football played in Canada in which two teams of 12 players each compete for territorial control of a field of play 110 yards (101 m) long and 65 yards (59 m) wide attempting to advance a pointed prolate spheroid ball into the opposing team's scoring area (end zone). In Canada, the term football usually refers to Canadian football and American football collectively, or either sport specifically, depending on the context. The two sports have shared origins and are closely related, but have significant differences—in particular, 12 players on the field per team in Canadian football rather than 11, and three downs per possession rather than four. The smaller number of downs in Canadian football results in less offensive rushing than in the American game.

Rugby football in Canada had its origins in the early 1860s, and over time, the unique game known as Canadian football developed. Both the Canadian Football League (CFL), the sport's top professional league, and Football Canada, the governing body for amateur play, trace their roots to 1884 and the founding of the Canadian Rugby Football Union. Currently active teams such as the Toronto Argonauts and Hamilton Tiger-Cats have similar longevity. The CFL is the most popular and only major professional Canadian football league. Its championship game, the Grey Cup, is the country's single largest sporting event, attracting a broad television audience (in 2009, about 40% of Canada's population watched part of the game). Canadian football is also played at the high school, junior, collegiate, and semi-professional levels: the Canadian Junior Football League and Quebec Junior Football League are leagues for players aged 18–22, many post-secondary institutions compete in Canadian Interuniversity Sport for the Vanier Cup, and senior leagues such as the Alberta Football League have grown in popularity in recent years. Great achievements in Canadian football are enshrined in the Canadian Football Hall of Fame.