Lang was first elected in 1976 and served 22 years as mayor before stepping down in 1998.
He served as a city councillor for 13 years prior to becoming mayor.
During Lang’s reign as mayor, Côte Saint-Luc built a new arena and a combined library and City Hall complex, renamed the Bernard Lang Civic Centre upon his retirement.
According to the City of Côte Saint-Luc's website, Lang's credo was "service in beautification and reasonable cost."
In 2005, on the cusp of 80, the retired mayor attempted a comeback in order to address the demerger crisis then facing Côte Saint-Luc.
He lost to the city's current mayor, Anthony Housefather.
The defeat was difficult for Lang, says his friend and current Côte Saint-Luc city councillor, Mike Cohen.
“There was just a tremendous passion for what he did,” Cohen told CBC News.
His disappointment, however, was soon overcome by his desire to continue his work for the city, which he did as a member of numerous committees.
And despite the loss to Housefather, Cohen says people never stopped calling him Mayor Lang.
Lang was a lifelong Montrealer who earned two degrees in Engineering from McGill University. He was also active in Jewish community life.
He served in the Canadian Army during the Second World War and then went to work with Rolls Royce of Canada, where he served as chief service engineer on turbo-prop engines.
He eventually opened his own air-conditioning and energy conservation business.
Lang first moved to Côte Saint-Luc with his wife Miriam in 1955.
His coffin will be draped in the city's flag at his funeral on Sunday.