Michel Aumont belongs to the brotherhood of the actors of the comedy of discomfort, fully willing to and capable of interpreting the most challenging roles, straddling at the same time between the heartbreaking and the derisive, between the natural and the complex, and finally between the distressing and the entertaining.
At the Conservatoire national d’art dramatique (National Conservatory of Dramatic Arts) of Paris, he attended the classes of Denis d'Inès and of Jean Debucourt. In the 1956 competition, he was awarded a first prize for Modern Comedy in Chekhov's A Tragedian in Spite of himself and another first prize for Classic Comedy in the role of The Doctor in Molière’s_The Jealousy of le Barbouillé (La Jalousie du barbouillé)_.

On graduating from the Conservatoire, he was hired as a pensionnaire at the Comédie-Française on September 1, 1956, and was named a sociétaire on January 1, 1965, then a sociétaire honoraire in January 1994. His contract stipulated that he would play the roles specific to "character study," that is the old barons, which he brilliantly did in spite of his youth. He, therefore, was familiar with the miscellany of Géronte characters in Scapin the Schemer, in The Doctor in Spite of Himself, and in Regnard’s The Sole Heir (Le Légataire universel), but it was in Harpagon (Molière’s The Miser), a role heplayed for twenty years.
Among the chief roles he embodied, we can name numerous characters from plays by Molière, Shakespeare, Beaumarchais, Feydeau, Labiche, Courteline, Balzac, Becque, and even the characters of contemporary authors such as Giraudoux, Ionesco, and Beckett, whom he particularly liked. He gradually emerged from the character study thanks to his friend Jean-Paul Roussillon and set his true face free of the makeup and the hairpieces to emerge "without any adornment.” Simplicity and depth then take precedence over artificial makeup and design.

At the Comédie-Française, he mainly worked with Roger Blin, Jean-Paul Roussillon, Terry Hands, Antoine Vitez, Claude Régy, Jean-Pierre Vincent and Jorge Lavelli.
In 1972, he played the role played by Robert Hirsch in Richard III in Avignon, which earned him a triumphant success in a tragic role.
He created a host of roles at the Comédie-Française, at the Salle Richelieu or at the Odeon, most notably Amalric in Claudel's Partage de Midi (The Break of Noon) in 1975, Jean Puntila in Brecht’s Master Puntilla and His Valet Matti (1976), Berenger in Ionesco’s The King Is Dying (1975), Vladimir in Beckett’s Waiting for Godot (1978), Trigorin in Chekhov's The Seagull (1980), Hamm in Beckett’s Endgame (1988), Garcin in Jean-Paul Sartre’s_Behind Closed Doors (1990), Mercadet in Balzac’s Le Faiseur (1993).
His friendship with Jean-Paul Roussillon gave birth to spectacles of a memorable intensity, such as those of_Amorphe d'Ottenburg by Jean-Claude Grumberg, La Nostalgie, camarade... by François Billetdoux, and Abel et Belo by Robert Pinget.
In 2005, he played in Dieu est un steward de bonne composition by Yves Ravey directed by Jean-Michel Ribes at the Théâtre du Rond-Point. In 2007, he appeared in Vincent Delecroix’s At the Door (À la porte) directed by Marcel Bluwal at the Théâtre de l'Œuvre and in Woody Allen’s Puzzle directed by Annick Blancheteau and Jean Mourière at the Théâtre du Palais-Royal. In 2010, he played in Lionel Goldstein’s David & Edward staged by MarcelBluwal at the Théâtre de l'Œuvre.

In addition to his continuing career in the theater, Michel Aumont has led a stunning career in the cinema, taking on the roles of the "eccentric character," the reason why, not surprisingly so, the best amateurs of figures seek him as an actor, namely Michel DevilIe, Claude Chabrol, Bertrand Tavemier, Francis Veber, and Pascal Thomas.
He has played in Palais Royal! directed by Valérie Lemercier (2005), in The Valet (La Doublure) by Francis Veber (2006), in Park Benches (Bancs publics – Versailles Rive-Droite) directed by Bruno Podalydès (2009), and, in 2010, in Comme les 5 doigts de la main directed by Alexandre Arcady, in Imogène McCarthery directed by Alexandre Charlot and Franck Magnier, and in A View of Love (Un balcon sur la mer) directed by Nicole Garcia.
He gives to his characters this right dose of humanity and a unique presence, which make him stand out on all occasions, including in figuration.