Saint-Polycarpe is a municipality located in the Vaudreuil-Soulanges Regional County Municipality in the Montérégie region west of Montreal, Quebec, Canada, and just east of the Quebec-Ontario border. It was named for Polycarp, a 2nd-century bishop of Smyrna. The population as of the 2021 Canadian Census was 2,372. While a parish during the 18th century, its territory included portions of what is now part of Saint-Zotique.