Forty years ago on Sept. 1, three men set fire to the building after being turned away from Wagon Wheel bar, which operated in the same space as the café after the café closed. Many people died because of a lack of fire exits.
Since then, the city has updated its building codes.
"They changed the regulations for the inspection of the buildings … but most of all, you have to have exits," said Montreal Mayor Gérald Tremblay.
The memorial, a long piece of granite that runs along the edge of Phillips Square, bears the names of the 37 people who lost their lives in the blaze.
Survivors and family members of those who died are expected to take part in more ceremonies on Saturday.