The woman was struck by a vehicle turning left on to Parc from St-Viateur Street, Montreal police said.
Const. Manuel Couture said the vehicle, driven by a 31-year-old man, was travelling at a low speed at the time of the collision.
The woman, who police say is in her 80s or 90s, suffered head injuries and was taken to hospital in critical condition.
Parc Avenue remains closed between St-Joseph Boulevard and Bernard Avenue as police investigate.