Maurice Ronet was born in Nice, Alpes Maritimes, the son of professional actors Émile Robinet and Gilberte Dubreuil. He studied at the Paris Conservatoire where Jean-Louis Barrault was one of his mentors. He made his fim debut in Jacques Becker's Rendez-vous de juillet (1949), at the age of 22. Shortly thereafter, he married actress Maria Pacôme and departed to southern France to try his hand at ceramics, painting, writing and music. Throughout the early 50's he made his living by selling his paintings and acting in supporting roles in the films of directors like Yves Allégret, René Wheeler and Yves Ciampi, with ambitions of becoming a director. However, he came to discover a freedom in acting and a creative satisfaction that provided a synthesis of all that interested him in painting and literature.
He first garnered acclaim at the Cannes Film Festival, in 1953, for his work in Jean Dreville's Horizons sans fin (Endless Horizons) and over the next few years, notably as the romantic lead in André Michel's La Sorcière (The Scorceress, 1956) and in Jules Dassin's follow-up to Rififi, Celui qui doit mourir (He Who Must Die, 1957). It was at the presentation La Sorcière, at Cannes in 1956, that Ronet met a creative and intellectual counterpart in Louis Malle. Ronet made his international box-office breakthrough as Julien Tavernier in Malle's first feature film, Ascenseur pour l'échafaud (Elevator to the Gallows, 1957).
He went on to act in close to one hundred French and Spanish, Italian, British & American co-productions of the 50s, 60s, 70's and 80's, in leading and in smaller and/or comedic character roles, notably: Plein Soleil (Purple Noon; 1960, Rene Clement); La Dénonciation (1962, Jacques Doniol-Valcroze); Malle's and Ronet's finest work of that period - Le Feu follet (The Fire Within, 1963), which won the Special Jury Prize at the Venice Film Festival and was nominated for an Academy Award for Best Foreign Language Film; Claude Chabrol's The Champagne Murders (Le Scandale) for which he won the Best Actor award at the 1967 San Sebastián International Film Festival & La Femme infidèle (The Unfaithful Wife, 1968); Jacques Deray's La Piscine (The Swimming Pool, 1969);
Michel Deville's Raphaël ou le débauché (1971) and Bertrand Blier's Beau-père (1981).
He appeared multiple times in the films of Chabrol, Alexandre Astruc and René Clément and co-starred with French film icons of legend (but, arguably, no greater talent or versatility) like Alain Delon, Brigitte Bardot and Jeanne Moreau.
He made his directorial debut in 1964 with Le Voleur de Tibidabo, a light-hearted crime story shot in Barcelona, and followed it up with two documentaries Vers l'île des dragons (1974), an allegorical journey to Indonesia to film the Komodo dragon and a report on the building of a damn in Caborabassa, Mozambique, for French television. Toward the end of his life he directed more programs for television: an acclaimed adaptation of Herman Melville's Bartleby in 1976 and adaptations of Edgar Allan Poe & Cornell Woolrich stories. He also authored two books: "L'ile des Dragons" (1973) and "Le Métier de Comédien" (1977), an honest and thorough discussion of the acting profession.
His marriage to Maria Pacôme ended in a separation and, finally, divorce in 1956. He lived with Josephine Chaplin in Lubéron in Provence, by whom he had a son, Julien (b.1980), from 1977 until his death, of cancer, a month before what would have been his 56th birthday.