Côte-Sainte-Catherine lock, Navigation lock in Sainte-Catherine, Canada.

The Côte-Sainte-Catherine lock is a navigation structure in Sainte-Catherine that lifts vessels approximately 9 meters. It allows ships to pass beyond the Lachine Rapids and gain access to Lake Saint-Louis.

The Côte-Sainte-Catherine lock was inaugurated on 26 June 1959 by Queen Elizabeth II, the same year the Saint Lawrence Seaway became operational in its current form. Its construction required moving 54 houses along Boulevard Marie-Victorin in Sainte-Catherine. The lock is part of the South Shore Canal, a 14-nautical-mile link between the Port of Montreal and Lake Saint-Louis.

The lock takes its name from the Côte-Sainte-Catherine shore where it stands, and its grounds border Île du Seigneur, laid out as the Parc de la Côte-Sainte-Catherine. From the banks visitors watch lakers and pleasure craft rise 9 metres in the chamber, a sight tied to the Seaway season that runs from mid-March to late December.

The lock chamber measures 233.5 m long, 24.4 m wide and 9.1 m deep, raising ships 9 m to the upstream canal. The Seaway season runs from mid-March to the fourth week of December, with the closing day varying each year. The lock lies between Île de la Voie Maritime and Île du Seigneur, the latter laid out as Parc de la Côte-Sainte-Catherine.

The lock lies between Île de la Voie Maritime and Île du Seigneur, the latter laid out as Parc de la Côte-Sainte-Catherine. Building it required moving 54 houses along Boulevard Marie-Victorin in Sainte-Catherine. It sits downstream of the Beauharnois lock of the Beauharnois Canal.