Bernard Jean Wilen, known as Barney Wilen, was born in Nice on March 4, 1937, the son of an American father, a dentist turned inventor, and a French mother. His father's American citizenship let the family spend the war years in the United States, where he began learning the saxophone, and they returned to the Riviera afterwards. The writer Blaise Cendrars, a friend of his mother, urged him toward music, and as a teenager he played in Nice clubs and started a youth jazz club in the city. In 1953 he moved to Paris and became a regular at the club Le Tabou beside Jimmy Gourley, Bobby Jaspar and Henri Renaud and the American musicians passing through. His first recordings date from 1955, as a sideman with Jay Cameron and with Roy Haynes.

His breakthrough came in 1957. When Miles Davis was in Paris to write the music for Louis Malle's first feature, Ascenseur pour l'échafaud, he hired the twenty-year-old Wilen on tenor saxophone, with the pianist René Urtreger, the bassist Pierre Michelot and the drummer Kenny Clarke. The band played in a single night in front of a screen showing the film. The same year Wilen made Tilt, his first album as a leader, recorded in Paris in January 1957 with the pianist Maurice Vander among others, and in 1958 the Académie du Jazz gave him its Prix Django-Reinhardt. In 1959 he appeared at the Newport Jazz Festival with the pianist Toshiko Akiyoshi, the bassist Tommy Bryant and Roy Haynes, and recorded Jazz sur Seine with Kenny Clarke, Milt Jackson and Percy Heath. He also wrote and played the music for Édouard Molinaro's film Un témoin dans la ville, recorded in Paris with the trumpeter Kenny Dorham, and played in the soundtrack for Roger Vadim's Les Liaisons dangereuses as the tenor saxophonist of Art Blakey's Jazz Messengers, alongside Lee Morgan and Bobby Timmons (he also plays soprano on one track, where Duke Jordan is the pianist); Thelonious Monk recorded his own version of the music in Paris with Wilen in the band.

In the mid and late 1960s he moved away from his bebop roots. He recorded Zodiac for Vogue in 1966, twelve short pieces with Karl Berger on vibraphone, Jean-François Jenny-Clark on bass and Jacques Thollot on drums, played with the Swedish trombonist Eje Thelin, joined the pianist François Tusques's pioneering French free-jazz sessions, and made Jazz Meets India (SABA, 1967) with the Swiss pianist Irène Schweizer and the German trumpeter Manfred Schoof. His two albums for MPS in 1968 were Auto Jazz, a tribute to the racing driver Lorenzo Bandini, and Dear Prof. Leary, made with a group called the Amazing Free Rock Band and dedicated to Timothy Leary; the second has been cited as one of the records that sketched the principles of jazz fusion.

In 1969 Wilen left Europe for Africa with a party of travelers, among them his then partner Caroline de Bendern, aiming for Zanzibar. The trip lasted two years, and it became the material for Moshi (Saravah, 1972), a mix of jazz and African music that sold poorly; Pierre Barouh later called it a superb album that went unnoticed. Wilen then stayed out of the recording studio for most of the 1970s. He settled again in Nice, where he produced and organized local jazz events, worked with punk musicians, and in the early 1980s launched the label AAAA with the singer and visual artist Marie Möör, who became his partner.

The comeback began in the late 1980s. A comic strip by Loustal and Philippe Paringaux, Barney et la note bleue, was freely inspired by his life, and Wilen answered with the album La Note bleue (IDA, 1987), recorded in December 1986 with the pianist Alain Jean-Marie, the bassist Riccardo Del Fra, the drummer Sangoma Everett and the guitarist Philippe Petit. He wrote film music for French directors again, toured Japan for the first time in 1990, and recorded steadily through the first half of the decade: Paris Moods with a quartet that included the young pianist Jacky Terrasson (July 1990), Movie Themes from France with the pianist Mal Waldron (October 1990), duets with Alain Jean-Marie, a live set with the Catalan pianist Tete Montoliu at the Grenoble Jazz Festival in 1988 that stayed in the archive until 2020, and albums for the Japanese label Venus. By the mid 1990s he was leading a bebop-minded band with the pianist Laurent de Wilde. Barney Wilen died in Paris on May 25, 1996, at the age of 59.

He remains a French jazz touchstone. Georges Perec named him in Je me souviens (1978), Stéphane Sinde's documentary Barney Wilen, the rest of your life appeared in 2006, and Yves Buin published a biography in 2017. His working life was spent in France: he grew up on the Riviera, built his career in Paris and Nice, and recorded most of his own albums there.

Wilen was a tenor saxophonist first, with some soprano, whose playing came out of the bebop and hard bop of the Paris scene of the 1950s, and whose later albums leaned on ballads and standards, among them French Ballads (1987) and Essential Ballads (1993). AllMusic classes him as hard bop, post-bop and mainstream jazz and lists Sonny Rollins, John Coltrane, Charlie Parker, Lucky Thompson, Al Cohn, Illinois Jacquet and Ben Webster among his related artists. What set him apart from other French players of his generation was how far he followed the music out of that mold: into free improvisation and electric, rock-driven jazz in the late 1960s, into jazz-and-African-music experiments in the early 1970s, and back to the bebop repertoire at the end of his life. He also composed regularly for French cinema.