The Montreal Metro (French: Mtro de Montral) is a rubber-tired underground rapid transit system serving Greater Montreal, Quebec, Canada. The metro, operated by the Socit de transport de Montral (STM), was inaugurated on October 14, 1966, during the tenure of Mayor Jean Drapeau.

It has expanded since the 1960s from 26 stations on three separate lines to 68 stations on four lines totalling 69.2 kilometres (43.0 mi) in length, serving the north, east and centre of the Island of Montreal with connections to Longueuil, via the Yellow Line, and Laval, via the Orange Line.

The Montreal Metro is Canada's second busiest rapid transit system and North America's fourth busiest rapid transit system, behind the New York City Subway, the Mexico City Metro and the Toronto subway, delivering an average of 757,200 daily unlinked passenger trips per weekday as of the second quarter of 2022. In 2021, 164,943,900 trips on the Metro were completed. According to the STM, the Metro system had transported over 7 billion passengers as of 2010. With the Metro and the REM, Montreal has built one of North America's largest urban rapid transit schemes, attracting the second-highest ridership per capita behind New York City.

Montreal ( (listen) MUN-tree-AWL; officially Montréal, French: [mɔ̃ʁeal] (listen)) is the second-most populous city in Canada and most populous city in the Canadian province of Quebec. Founded in 1642 as Ville-Marie, or "City of Mary", it is named after Mount Royal, the triple-peaked hill in the heart of the city. The city is centred on the Island of Montreal, which obtained its name from the same origin as the city, and a few much smaller peripheral islands, the largest of which is Île Bizard. The city is situated 196 km (122 mi) east of the national capital Ottawa, and 258 km (160 mi) southwest of the provincial capital, Quebec City.

As of 2021, the city had a population of 1,762,949, and a metropolitan population of 4,291,732, making it the second-largest city, and second-largest metropolitan area in Canada. French is the city's official language and in 2016 was the only home language of 53.7% of the population, while 18.2% spoke only English and 18.7% spoke neither French nor English at home. 9.4% spoke a mix of French, English and a foreign language at home. In the larger Montreal Census Metropolitan Area, 71.2% of the population spoke at least French at home, compared to 19.0% who spoke English. Still in 2016, 87.4% of the population of the city of Montreal considered themselves fluent in French while 91.4% could speak it in the metropolitan area. Montreal is one of the most bilingual cities in Quebec and Canada, with 57.4% of the population able to speak both English and French. Montreal is the second-largest primarily French-speaking city in the developed world, after Paris.Historically the commercial capital of Canada, Montreal was surpassed in population and in economic strength by Toronto in the 1970s. It remains an important centre of commerce, aerospace, transport, finance, pharmaceuticals, technology, design, education, art, culture, tourism, food, fashion, video game development, film, and world affairs. Montreal has the second-highest number of consulates in North America, serves as the location of the headquarters of the International Civil Aviation Organization, and was named a UNESCO City of Design in 2006. In 2017, Montreal was ranked the 12th-most liveable city in the world by the Economist Intelligence Unit in its annual Global Liveability Ranking, although it slipped to rank 40 in the 2021 index, primarily due to stress on the healthcare system from the COVID-19 pandemic. It is regularly ranked as a top ten city in the world to be a university student in the QS World University Rankings.Montreal has hosted multiple international conferences and events, including the 1967 International and Universal Exposition and the 1976 Summer Olympics. It is the only Canadian city to have held the Summer Olympics. In 2018, Montreal was ranked as a global city. The city hosts the Canadian Grand Prix of Formula One since 1978, as well as the Montreal International Jazz Festival, the largest jazz festival in the world, the Just for Laughs festival, the largest comedy festival in the world, and Les Francos de Montréal, which is the largest event devoted exclusively to French-language music anywhere in the world. It is also home to ice hockey team Montreal Canadiens, the franchise with the most Stanley Cup wins.