Complexe Chaussegros-de-Léry, Architectural structure in Old Montreal, Canada.

The Complexe Chaussegros-de-Léry consists of two buildings on Rue Notre-Dame Est, opened in 1992 and owned by the City of Montreal through the SHDM. Édifice I at 303 is an office building for the city administration, designed by architect Dan Hanganu. Édifice II at 309-329 combines commercial and residential uses.

The complex opened in 1992 as a set of two buildings owned by the City of Montreal through the Société d'habitation et de développement de Montréal. Phase I, the office building at 303 rue Notre-Dame Est, was designed by architect Dan Hanganu. The whole complex is named in honour of Gaspard-Joseph Chaussegros de Léry.

The complex takes its name from Gaspard-Joseph Chaussegros de Léry, the engineer behind Montreal's 18th-century fortifications. Its two buildings at 303 and 309-329 rue Notre-Dame Est were opened in 1992 and are owned by the city through the Société d'habitation et de développement de Montréal, which runs the office and residential-commercial halves.

The complex stands on Rue Notre-Dame Est in Ville-Marie, with two separate addresses: 303 for the office building and 309-329 for the commercial and residential one. The two buildings face the same street, so both are found by walking along Notre-Dame Est rather than through a shared entrance.

The building brings together three completely different functions within a single structure in an unusual way. This mixture of government offices, shops, and homes in close proximity is less common than one might expect.