Châteauguay—Saint-Constant is a federal electoral district in Quebec, Canada, that has been represented in the Canadian House of Commons since 2004. Its population in 2006 was 107,165.
Châteauguay—Saint-Constant was created in 2003 from Châteauguay riding, with the exception of a portion of Châteauguay that was transferred in Beauharnois—Salaberry and Saint-Jean ridings.
The district includes all of the Regional County Municipality of Rousillon including Kahnawake Indian Reserve No. 14, but excluding the cities of Candiac and La Prairie and the Municipality of Saint-Philippe in the east of the county municipality. The neighbouring ridings are Vaudreuil—Soulanges, Beauharnois—Salaberry, Brossard—La Prairie, LaSalle—Émard, Notre-Dame-de-Grâce—Lachine, and Lac-Saint-Louis.
This riding has elected the following Members of Parliament:
| Parliament | Years | Member | Party | |
|---|---|---|---|---|
| Châteauguay prior to 2003 | ||||
| 38th | 2004-2006 | Denise Poirier-Rivard | Bloc Québécois | |
| 39th | 2006- | Carole Freeman | Bloc Québécois | |