Saint Pierre Island is one of the three main islands of Saint Pierre and Miquelon. It contains the town of Saint-Pierre, which lies on the island's east coast and is the main population centre of the island group.
Several smaller islands lie off the coast of Saint Pierre, notably L'Île-aux-Marins and L'Île-aux-Vainqueurs, both to the east, and Grand Colombier, which lies off Saint Pierre's northernmost point. Saint-Pierre and its neighboring islands form the Saint-Pierre commune, one of two communes in Saint Pierre and Miquelon (the other being Miquelon-Langlade).