Ice hockey, simply referred to as "hockey" in both English and French in Canada, dates back to the 19th century. The sport is very popular and played year-round and at every level in the country. Born of various influences from stick-and-ball games brought from the United Kingdom and indigenous games, the contemporary sport of hockey originated in Montreal, Quebec, and Halifax, Nova Scotia. It is the official national winter sport of Canada. Hockey is widely considered Canada's national pastime, with high levels of participation by children, men, and women at various levels of competition. As of 2021, over 15 million people in Canada followed the National Hockey League.

The game of ice hockey has its roots in the various stick-and-ball games played over the centuries in the United Kingdom and North America. From prior to the establishment of Canada, Europeans are recorded as having played versions of field hockey and its relatives both on grass and on ice, while the Mi'kmaq indigenous peoples of the Maritimes also had a ball-and-stick game, and made many hockey sticks used by Europeans in the 1800s. Similarly, ice skating team games which eventually became the organized sport of bandy were also played. From these roots, the contemporary sport of hockey was developed in Canada, most notably in Montreal, Quebec, and Halifax, Nova Scotia. Though games of hockey were reported to have been played previously in places like Deline, Northwest Territories, Windsor and Kingston, Ontario, and on Chippewa Creek, in the Niagara region of Ontario, Montreal was the site of the first indoor hockey game recognized by the International Ice Hockey Federation (IIHF). The game was played on March 3, 1875, at the Victoria Skating Rink, organized by James Creighton, a McGill University student from Halifax, using rules imported from the Maritimes. The first commercially made hockey skates were produced in Halifax and the hockey sticks used in the first recognized hockey game were designed jointly by Haligonians and Mi'kmaq. Some characteristics of modern hockey, such as the length of the ice rink and the use of a puck, were developed in that game. Additional technical improvements to that first game came from Nova Scotia, such as the addition of fishing nets and sticks to prop them up replacing stones on the ice as the goal and the introduction of goaltender equipment borrowed from the game of cricket. The rules developed by the Canadians were later adopted by foreign hockey-playing nations.

Annual championships began in Montreal in the 1880s, leading to the awarding of the Stanley Cup, considered the oldest trophy in North American sports. Lord Stanley of Preston was appointed by Queen Victoria to be the Governor General of Canada on June 11, 1888. While governor general, hockey was still just forming in Canada. He first got to see the game of hockey played at Montreal's 1889 Winter Carnival. During the carnival he watched the Montreal Victorias play the Montreal Hockey Club. Afterwards, Stanley and his family became very involved in the game of hockey. His two sons, Arthur and Algernon, convinced their father to donate a trophy that would be considered to be a visible sign of the hockey championship, which was a silver bowl inlaid with gold. The trophy was first presented in 1893 and was called the Dominion Hockey Challenge Cup. The name of the trophy has since been known as the Stanley Cup.

Professionalism began in the 1890s, with players being paid under the table in various sports, including hockey and lacrosse. By the end of the decade, the predominant amateur league was the Amateur Hockey Association of Canada (ACHA), which Lord Stanley decreed its champions must take part in the cup finals. Dominated by Montreal teams in its early years, the first Western Canada team to mount a challenge were the Winnipeg Victorias. In 1899, the AHCA changed its name to the Canadian Amateur Hockey League. Openly professional leagues emerged after 1900. Early professional play took place in Northern Ontario and in the Maritimes (the Coloured Hockey League) along with leagues in Central and Western Canada. Although many Canadian amateur teams paid their players covertly, most Canadian hockey associations still stuck to the codes of amateurism. Five cities in the United States formed the International Professional Hockey League (IPHL) in 1904. The American-based league was the beginning of professional hockey. The IPHL attracted high-end Canadian players, depriving Canada of some of its best players. The IPHL ceased after three years, but that was long enough to spark the creation of a Canadian-based professional league, the Ontario Professional Hockey League, in 1908. Though some believe the IHL's short existence was due to lack of spectator interest, the primary reason the league failed was a loss of good players back to Canadian teams that by 1906 played in hockey associations, such as the Eastern Canada Amateur Hockey Association, that allowed professionals to play alongside amateurs. The violence of the sport instigated the Ottawa Silver Seven and Montreal Wanderers rivalry of 1907. Newspapers described hockey as a combination of "brutal butchery" and "strenuous spectacle," speaking to public perceptions and different ways of experiencing the game. Ideals of respectable, middle-class masculinity and rough, working-class masculinity co-existed within accounts of fast, skilled, rugged, hard-hitting hockey.

In 1908, Sir Montagu Allan instituted the Allan Cup to be awarded to the best amateur Canadian hockey team, while the Stanley Cup would continue to be awarded to the best Canadian team overall. The National Hockey Association (NHA) was formed in 1910 for professional teams in Eastern Canada, while Lester and Frank Patrick formed the Pacific Coast Hockey Association (PCHA) in Western Canada in 1911. The NHA later morphed into the National Hockey League (NHL) in 1917. In 1917, teams from the PCHA were capable of challenging for the Stanley Cup and in 1918, the Vancouver Millionaires were the first Canadian Pacific team to challenge for the trophy. In 1921, the professional West Coast Hockey League (WCHL) was established and the Victoria Cougars of the WCHL were the first professional Western Canada team to win the award in 1925. However, by 1927, the PCHA and the WCHL were bankrupt and the NHL dominated professional hockey throughout North America. The Montreal Canadiens and Toronto Maple Leafs are two of the NHL's oldest franchises, and its two most successful; the Canadiens have won the Stanley Cup 24 times, and the Maple Leafs 13.

During the 1920s, Winnipeg's senior hockey league champions for the 1919–20 season, the Winnipeg Falcons, featuring Icelandic Canadians, became Canadian national champions and won the 1920 Olympic gold medal for Canada at Antwerp, Belgium. With their devotion to Canada in the First World War, their integration made this team a symbol of Canadian masculinity, unaffected by the ethnic stereotyping and discrimination that affected some other sports teams during the 1920s. During the Great Depression, the Canadian Amateur Hockey Association was forced to re-evaluate its position on amateurism in hockey and to assess its relationship to the amateur sports infrastructure in Canada, which was headed by the Amateur Athletic Union of Canada. The lacklustre performance of the Canadian national hockey team at the 1936 Olympics, over player availability forced radical changes on approaches to how the game was formulated in the country. The Canadian national men's team dominated international amateur play from the 1920s until the early 1950s, when the introduction of state-sponsored national hockey programs, notably from the Soviet Union, began to dominate over the club-based Canadian program. Canada would change to a national team composed of amateurs and eventually withdraw from international senior-level competition in a dispute over the introduction of professionals, considered Canada's best, to counter the dominance and provide an "even playing field" in the eyes of Canadian hockey officials.

In 1971 the professional World Hockey Association (WHA) was formed as a competitor to the NHL, playing in cities in Canada and the United States. Play began in 1972 and in an effort to lure players from the NHL, the WHA promised higher salaries and established franchises in under-served, mid-sized Canadian markets such as Calgary, Edmonton, Ottawa, Quebec City, and Winnipeg. The Avco Cup was awarded to the champion of the league and Winnipeg won the cup in the league's final year in 1979, as the league's teams went bankrupt. Attempts at a merger with the NHL began in 1977, but were derailed mainly by the owner of the Toronto Maple Leafs, Harold Ballard. However, in 1979, after reports of another failure to bring the teams in Edmonton, Quebec City and Winnipeg into the NHL made headlines and the owners of the Montreal Canadiens, Molson Brewery, had been one of the main opponents, a boycott across Canada began against Molson products and violence was directed towards company property in Monteal, Quebec City, and Winnipeg. This forced the Canadian House of Commons to intervene and support a motion urging the NHL to accept the three teams into the NHL. Eventually four of the WHA's franchises were folded into the NHL, including the three from Canada.

In September 1972, Canada's best hockey players from the NHL played the elite amateurs from the Soviet Union in an exhibition series. When Canadian prime minister Pierre Trudeau had met his Soviet counterpart, Alexei Kosygin, in 1971, their discussions included increasing the hockey competitions between the two countries. Soon after, hockey hierarchies of both nations decided on a series of eight games, four to be played across Canada and four in Moscow. For Canadians, the Summit Series was intended to be a celebration of their global supremacy in hockey. The architects of Soviet hockey, on the other hand, had designs on surprising Canada and the world with their skill and claiming the Canadian game as their own. The Summit Series was the catalyst for a re-examination of the Canadian hockey system, organization, coaching, and training methods. The changes in Canadian hockey, along with the acceptance of professional players in international play, would eventually lead to a return to international competition in the 1990s, culminating in Canada's first gold medal victory at the 2002 Winter Olympics in 50 years and repeating the feat at home in Vancouver in 2010.