Lower Normandy (French: Basse-Normandie, IPA: [bas nɔr.mɑ̃.di]; Norman: Basse-Normaundie) is an administrative region of France. It was created in 1956, when the Normandy region was divided into Lower Normandy and Upper Normandy. The region includes three departments, Calvados, Manche and Orne, that cover the part of Normandy traditionally termed "Lower Normandy" lying west of the Dives River, the Pays d'Auge (except a small part remaining in Upper Normandy), a small part of the Pays d'Ouche (the main part remaining in Upper Normandy), the Norman Perche and part of the "French" Perche. It covers 10,857 km², 3.2 percent of the surface area of France.

The traditional districts of Lower Normandy include the Cotentin Peninsula and La Hague, the Campagne de Caen, the Norman Bocage, the Bessin and the Avranchin.

The traditional province of Normandy, with an integral history reaching back to the 10th century, was divided in 1957 into two regions: Lower Normandy and Upper Normandy.

During the Roman era, the region was divided into several different city-states. That of Vieux was excavated in the 17th century, revealing numerous structures and vestiges bearing testimony to the prosperity of the Caen region.