Saint-Laurent shares its name with the great river baptized by Jacques Cartier when he to make his way up it on August 10, 1535, on the feast of Saint Laurent.

The Sulpicians gave the name of coste St. Laurent to a country road that ran east-west in the center of the island, along the route of the present-day Metropolitan highway. As development along the road increased, it naturally lent the name St. Laurent to first the parish, then the village, the parish municipality in 1845 and finally the town of St. Laurent when it was incorporated in 1893.

Source: City of Montréal