Perrin was born in Paris. His father, Alexandre Simonet, was a theatre director and his mother, Marie Perrin, was an actress. He is also the nephew of the actor Antoine Balpêtré . Perrin was trained as an actor at the Conservatoire National Supérieur d'Art Dramatique.
He was given his first juvenile film roles by Italian director Valerio Zurlini. He also gave over 400 performances of L'Année du bac on the Paris stage.
He played opposite Claudia Cardinale in the romantic comedy La Ragazza con la valigia and played the younger brother in Family Diary with Marcello Mastroianni, both under the direction of Zurlini. He was also the adult Salvatore in the international hit Cinema Paradiso. He then plays several roles in films of Henri-Georges Clouzot (The Truth in 1960), Mauro Bolognini (Corruption in 1963). He plays leading roles in for films by Pierre Schoendoerffer : La 317e Section (1965), Le Crabe-tambour (1977), A Captain's Honor (1982) and Là-haut, un roi au dessus des nuages (2004). He also plays beside Catherine Deneuve in two musical movies by Jacques Demy : The Young Girls of Rochefort (1967) and Donkey Skin (1970).
He won two Best Actor awards at the Venice Film Festival in 1966 for the Italian film Almost a Man and the Spanish film The Search.
At 27, he created a studio and produced and acted in Z, directed by Costa Gavras and starring Jean-Louis Trintignant, Yves Montand, and Irene Papas. Z received an Oscar for Best Foreign Film in 1969.
He collaborated with Costa Gavras again in État de Siège (State of Siege) in 1973 and Section spéciale in 1975. Both films had political themes, and Perrin continued this trend with a documentary on the Algerian uprising (La guerre d'Algérie) and a film on the Chilean presidency of Salvador Allende (La Spirale). In 1973 Perrin produced - and starred alongside Claude Jade as his love interest - the first film of Benoît Lamy, Home Sweet Home. The film acclaimed 14 international awards.
Perrin produced another Oscar-winning film in 1976: La Victoire en chantant (Black and White in Color) by director Jean-Jacques Annaud. In 1977, he embarked on Le Désert des Tartares, again starring Trintignant. The cast included such big-name actors as Max von Sydow (it did win the Grand Prix du Cinéma Français).
He then devoted himself mainly to production with Microcosmos in 1995 and Le Peuple Migrateur (Winged Migration) in 2001, which were both filmed by his studio Galatée Films.
He also played the role of the old Pierre Morhange, narrator of the very internationally successful film The Chorus, that he also produced. The young Pépinot was played by his younger son Maxence.
He was made Knight of the Ordre national du Mérite in 1985, promoted Officer in 1997 and promoted Commander in 2003. He was made Knight of the Légion d'honneur in 1990 and promoted Officer in 2007.
He has three sons, Mathieu, born 1975, Maxence, born 1995, and Lancelot, born 2000. The two eldest are actors.