It was built in 1939 near Dorchester, Ontario, which was then outside the city limits of London but has since been annexed into the city. It was originally an air base under the command of the Commonwealth Air Training Plan, to train pilots from the British colonies and former colonies. It is now operated by the Greater London International Airport Authority.
The airport is the 12th busiest passenger airport in Canada, and its main runway is 8800 feet long. It serves Air Canada, Air Canada Jazz, Air Canada Vacations, Allegro Airlines, Northwest Airlines, Sunquest Vacations, WestJet Airlines, and Zip Air. It also provides services for cargo airlines.
Every June there an airshow is held at the airport, attracting aircraft and spectators from all over the world.