The Robert-Tatin Museum is an "art environment" created by the artist Robert Tatin, between 1962 and 1983, at the place called La Frénouse in Cossé-le-Vivien, in Mayenne.

At the origin of the site is an old house that the artist converted to live there with his wife. Over the years, he built an estate decorated with large sculptures in colored cement, drawing inspiration in particular from his travels and artistic currents of the past. The site is full of references to world religions, history and great artists. Robert Tatin had imagined it as a link between the civilizations of the East and those of the West.

The site became a museum open to visitors after the death of the artist. Exhibition halls present his paintings while spaces are left to current artists. The museum is one of the most visited in the Mayenne department and the Pays de la Loire region.