Marcillac is a commune in the Gironde department in southwestern France.
Marcillac may also refer to:
Marcillac AOC, an Appellation d'Origine Contrôlée for wine from the Aveyron department Marcillac-Vallon, a commune in the Aveyron department in southern France Marcillac-Lanville, a commune in the Charente department in southwestern France Marcillac-la-Croisille, a commune in the Corrèze department in central France Marcillac-la-Croze, a commune in the Corrèze department in central France Marcillac-Saint-Quentin, a commune in the Dordogne department in southwestern France Members of the House of La Rochefoucauld, whose titles include "Prince of Marcillac"