On Jan. 21, 1948, the blue and white fleur-de-lis was raised for the first time above Quebec City's National Assembly.
The government of Premier Maurice Duplessis was the first in Canada to official adopt a provincial flag.
The flag replaced the Red Ensign, which featured the British Union Jack.
President of Montreal's Saint-Jean-Baptiste Society, Mario Beaulieu, says the flag reaches beyond political and ideological differences, to symbolically unite all Quebecers.
He said he believes the adoption of the flag was a founding act for the Quebec people.
Today in Montreal, small flags will be handed out at various metro stations around the city during the morning rush hour to commemorate the anniversary.
At noon, there will be an assembly at Complexe Desjardins, followed by a parade that will end at Camille Laurin park.
There will also be several activities this afternoon and evening at Maison Ludger-Duvernay this afternoon, located at 82 Sherbrooke Street West. Author-songwriter Alexandre Belliard and the Eldéanne group will present a tribute to the fleur-de-lis and historian Marcel Tessier will host the evening program.