Décarie Interchange, Highway interchange in Montreal, Canada.

The Décarie Interchange is a freeway interchange on the Island of Montreal that links Autoroute 40 (Metropolitan Boulevard, also part of the Trans-Canada Highway) with Autoroute 15 south (Décarie Autoroute) and provides access to Boulevard Marcel-Laurin (Route 117) and Décarie Boulevard in the borough of Saint-Laurent. It marks the western end of the elevated Metropolitan Boulevard expressway, which descends to ground level to the west. Just west of it, the eastern terminus of Autoroute 520 merges into Autoroute 40 via a traffic circle.

The interchange was built during Montreal's infrastructure expansion in the 1960s to prepare the city for the 1967 Expo international exhibition. Construction was part of a broader transportation renewal program that readied the city for a major global event.

The structure takes its name from the Décarie family, whose member Daniel-Jérémie served as mayor of Notre-Dame-de-Grâce from 1877 to 1904. This naming reflects the area's local heritage and continues to define the identity of this major junction.

The interchange sits in the centre-west of the island of Montreal, where Autoroute 40 meets Autoroute 15 south and ramps lead to Boulevard Marcel-Laurin (Route 117) and Décarie Boulevard in Saint-Laurent. It is regularly congested at rush hour. Just west, Autoroute 520 (Côte-de-Liesse Expressway) merges into Autoroute 40 through a traffic circle, and the elevated Metropolitan Boulevard drops to ground level there.

The interchange is sometimes called the Décarie Circle in English-language Montreal radio traffic reports. Slightly west of it, the eastern terminus of Autoroute 520 merges into Autoroute 40 through a traffic circle and is sometimes counted as part of an extended Décarie Interchange area. The interchange also marks the western end of the elevated Metropolitan Boulevard expressway, which drops to ground level further west.