The Canadian International Air Show (CIAS) is an annual air show in Toronto, Ontario, Canada. The show is an aeronautical display of military, government and civilian aircraft, primarily from Canada and the United States. The show takes place along Toronto's waterfront for three days during the Canadian Labour Day weekend. The show began in 1946 and has been held at Exhibition Place since 1949.

Toronto was the site of numerous air shows as the city developed into a centre of air transportation and aircraft manufacturing in the early twentieth century. The Canadian International Air Show began in 1946 when the National Aeronautical Association of Canada attracted overflow crowds to a show at de Havilland Canada manufacturing plant at Downsview Airport. The show became an annual event. The air show moved to Exhibition Place in 1949. In 1956, the air show became affiliated with the annual Canadian National Exhibition (CNE).

The official CIAS takes place over the Canadian Labour Day Weekend, which coincides with the closing weekend of the CNE. The start time for the show is scheduled for 12:00 pm with the show ending at approximately 3:00 pm each afternoon. The CIAS practice session is usually held on the day before the official CIAS, taking place between 10:00 am and 2:00 pm

The show is performed over Lake Ontario directly south of Exhibition Place. It can be best viewed from Exhibition Place or Ontario Place, although the show is visible from any other lakefront site, especially Marilyn Bell Park or Coronation Park. Performers fly in from Pearson, as well as the island airport on nearby Toronto Islands.^{[citation needed]} Admission to the air show is free; however, viewing from Exhibition Place requires paid admission to the CNE.

There is no static display of aircraft. A photo tour at Pearson had been introduced in 1993 and a full static display in 1996. Although a success, the display was cancelled by the time of the 1998 air show.

In 2020, both the air show and that summer's Canadian National Exhibition were cancelled due to the global COVID-19 pandemic. In 2021, the air show took place, even though the CNE was cancelled.

The airshow is unpopular with some nearby residents who object to the noise created by the jet fighters participating in the show and others who object to the military participation. It has been noted that the noise of the jet fighter demonstrations specifically is similar to that experienced by persons in active war zones. In 2016, a Toronto Star columnist noted, "that in a city with a large population of refugee newcomers and people who have experienced the trauma of war it is insulting, invasive, and violent". Since 2012, during the airshow weekend, the Wikipedia article about the show has been repeatedly vandalized as a form of protest against the airshow, a phenomenon noted by the local Toronto media.

In 2021, Toronto City Councillor Joe Cressy called for an end to the air show and in 2023, Toronto Mayor Olivia Chow wrote air show organizers a letter saying: “Millions of Torontonians chose to take root in this City as a place of hope. A place of refuge. For many residents, the tremendous noise generated by high-powered jets flying overhead brings back unwanted memories of the violence and war they fled to call Toronto home.”