Marc Allégret (December 23, 1900 - November 3, 1973) was a French screenwriter and film director.

Born in Basel, Basel-Stadt, Switzerland, he was the elder brother Yves Allégret . Marc Allégret was educated to be a lawyer but after filming a 1927 trip to the Congo with his uncle André Gide, he chose to pursue a career in the motion picture industry. After working and training as an assistant director, in 1931 he directed his first feature, "Mam'zelle Nitouche" and the following year received much acclaim for his film, Fanny . He went on to a long career during which he wrote numerous scripts and directed more than fifty films.

Allégret is noted for discovering and/or developing new acting talent who went on to stardom including Michèle Morgan, Raimu, Gérard Philipe, Daniele Delorme Louis Jourdan, and Roger Vadim who would become his directing assistant.

He died in 1973 and was interred in the Cimetière des Gonards in Versailles, France.