Gérard Dédéyan (4 February 1942, Nantes) is a French professor of medieval history at the Paul Valéry University, Montpellier III, a member of the Armenian National Academy of Sciences and associate member of the Collège de France.
He studied Classical Armenian with Frédéric-Armand Feydit.In 1983, Gérard Dédéyan won the Prix Biguet of the Académie Française for his "Histoire des Arméniens".
Professor Charles Dédéyan was his father.