Laflèche (French pronunciation: [laflɛʃ]; originally known as Mackayville) is a neighbourhood in the Saint-Hubert borough of the city of Longueuil.

It is largely low-income, and similar to Ville LeMoyne and other parts of the Le Vieux-Longueuil borough.

A good proportion of the first inhabitants of the neighbourhood worked at the Canadian National plant in Pointe-Saint-Charles, which made it easier for workers to carry large pieces of wood in Laflèche to build houses.

With the opening of Jacques-Cartier Bridge in 1930 and the steadily increase of cars, many Montreal working families moved to the South Shore, including Mackayville.

Montreal and Southern Counties Railway had a tram stop in Mackayville at the corner Grande-Allée and Edouard.