Saint-Gilles is a municipality in Lotbinière Regional County Municipality in the Chaudière-Appalaches region of Quebec, Canada. Its population was 2,910 as of the Canada 2021 Census. The municipality has the largest surface area in Lotbinière Regional County Municipality, with a surface area of around 177.43 km2 and a population density of around 16.4 inhabitants/km2. Saint-Gilles is named after the seigneurie of Saint-Gilles of which it was part. It was granted in 1738 to Gilles Rageot de Beaurivage (1689-1754), an important merchant from Quebec.