Buffet was born in Paris and studied for two years at the École Nationale Superieure des Beaux-Arts. Afterwards he studied alone and from 1946 to 1949 had paintings shown in various Salons, sold a painting that was purchased by Doctor Girardin (who later left it to the Paris Museum of Modern Art), and signed an exclusive contract with Emmanuel David, which at the time was shared by Maurice Garnier.
From 1949 through 1955, Buffet received a variety of awards including first prize by the magazine Connaissance des arts, which named the 10 best post-war artists. From 1959 to 1955 to 1999, Buffet was exclusively with the Maurice Garnier Gallery.
In 1974 he was elected to the Académie des Beaux-Arts, and in 1988 an extension of the Bernard Buffet Museum was inaugurated in Japan. Buffet married and had three children, lived in Brittany, Paris, in a manor in Normandy.