Alain Creton, owner of Chez Alexandre, said city workers came by today and had him remove the outdoor furniture.
The City of Montreal says a 1.5-metre space should be left between a restaurant's façade and its terrasse to make it easier for people with limited mobility to get around.
Creton says Chez Alexandre has had a patio on the sidewalk for 38 years and no one ever had a problem with his terrasse until now.
He says removing it will cost him $6,000 a day in lost revenue.
"It's a lot of money and the tax I am paying for my restaurant is 40-thousand dollars every year," he told CBC.
Creton says he will also be forced to lay off at least 25 servers as a result of the closure.
He says he tried to contact the mayor's office today to find a solution, but hasn't heard back.
The terrasse will be able to open during Grand Prix weekend, when the street is closed.