The Palais de justice is a courthouse in Montreal, Quebec, Canada. It is located at 1 Notre-Dame Street East in the Old Montreal neighbourhood of the Ville-Marie borough. It was completed in 1971.

Though located in the Old Montreal historic district, it is an international style structure, featuring the outdoor sculpture Allegrocube. The black metal and granite building is adjacent to the Champ de Mars square. It was designed by Montreal architects Pierre Boulva and Jacques David, whose other prominent Montreal projects included 500 Place D'Armes, Théâtre Maisonneuve, the Dow Planetarium and the Place-des-Arts, Atwater and Lucien-L'Allier metro stations.

Created by Charles Daudelin in 1973, Allegrocube is a cube-shaped abstract sculpture outside the Palais, 2.4 m in height, made of bronze.

The current Palais de justice de Montréal is the third building on Notre-Dame Street in Old Montreal to bear that name. The first was the Old Montreal Courthouse, now known as the municipal Édifice Lucien-Saulnier, designed by John Ostell (as well as Frederick Preston Rubidge) and inaugurated in 1856. Construction on the second, now known as the Édifice Ernest-Cormier and home to the Quebec Court of Appeal, began in 1922.

• Old Montreal