Cap-Saint-Ignace is a municipality in the Montmagny Regional County Municipality within the Chaudière-Appalaches region of Quebec, Canada. It is located on the south shore of the Saint Lawrence River, 70 km east of Quebec City on Route 132.

Route 132 is the longest highway in Quebec. It follows the south shore of the Saint Lawrence River from the border with the state of New York in the hamlet of Dundee, west of Montreal to the Gulf of Saint Lawrence and circles the Gaspé Peninsula. This highway is known as the Navigator's Route. It passes through the Montérégie, Centre-du-Québec, Chaudière-Appalaches, Bas-Saint-Laurent and Gaspésie regions of the province.