Missillac (French pronunciation: [misijak] ⓘ; Gallo: Misilhac, Breton: Merzhelieg) is a commune located in the department of Loire-Atlantique in western France.

Missillac is located at the northwestern edge of Loire-Atlantique at the limit of the Morbihan 25 km from Saint-Nazaire, 65 km northwest of Nantes, and 25 km south of Redon.

The communes bordering Missillac are Sévérac, Saint-Gildas-des-Bois, Sainte-Reine-de-Bretagne, La Chapelle-des-Marais, Herbignac, and Pontchâteau.

The commune is crossed by the Nantes-Vannes expressway.

This Loire-Atlantique geographical article is a stub.