Bédier was born in Paris, France to Adolphe Bédier, a lawyer of Breton origin, and spent his childhood in Réunion. He was a professor of medieval French literature at the Université de Fribourg, Switzerland (1889–1891) and the Collège de France, Paris (c. 1893).
Modern theories of the fabliaux and the chansons de geste are based on two of Bédier's studies.
Bédier revived interest in several important old French texts, including Le roman de Tristan et Iseut (1900), La chanson de Roland (1921), and Les fabliaux (1893). He was a member of the Académie française from 1920 until his death.
His Tristan et Iseut was translated into Cornish by A. S. D. Smith, into English by Hilaire Belloc and Paul Rosenfeld, and into German by Rudolf G. Binding.
Bédier was also joint editor of the two-volume Littérature française, one of the most valuable modern general histories of French literature. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1929.
Bédier died in Le Grand-Serre, France