Metzger was born and raised in New York City. He received a B.A. in Dramatic Arts from City College of New York, where he studied with filmmakers Hans Richter and Leo Seltzer. He also studied acting privately with director Harold Clurman. During the Korean War, Metzger served in the U. S. Air Force with the 1350th Photographic Group, which interrupted his graduate studies at Columbia University.
In his early career, Metzger worked primarily as a film editor  employed in cutting trailers for Janus Films, a major distributor of foreign art films, especially those of Ingmar Bergman. His directorial debut, Dark Odyssey (1958) (co-directed with William Kyriakis) was a drama concerning the experiences of a Greek immigrant arriving in New York. The film was favorably reviewed by the New York Times.
Along with film distributor Ava Leighton, in 1961 Metzger founded Audubon Films, a film distribution company that specialized in importing international features, some of which were marketed into the gradually expanding sexploitation film genre. Metzger's skills as an editor were employed in re-cutting and augmenting many of the features Audubon handled, including I Spit on Your Grave Twilight Girls, and I, a Woman. Audubon's first run-away success was Mac Ahlberg's I, a Woman (U. S. 1966).
Metzger's second directorial effort, The Dirty Girls (shot in 1963 and released in 1965) marks his emergence as a major auteur in the sexploitation film genre. His subsequent films were often shot in Europe  ] and were adapted from novels or other literary sources, including La Dame aux Camellias, Carmen, Pygmalion, Therese and Isabelle, Naked Came the Stranger, and The Cat and the Canary. He cites John Farrow, Michael Powell and Orson Welles as influencing his work. His films have had scores written by composers including Piero Piccioni, Georges Auric, Georges Delerue and Stelvio Cipriani.
Under the pseudonym "Henry Paris", Metzger also directed several explicit pornographic features during the mid- to late-1970s. These films are typified by high production values, especially The Opening of Misty Beethoven (1975) and The Private Afternoons of Pamela Mann (1975) and are generally critically celebrated. Some were also released in softcore versions.
With his 1978 feature The Cat and the Canary, Metzger distinguished himself as one of the few adult film auteurs to direct a dramatic feature outside of the sexploitation film genre. The film starred Honor Blackman and Carol Lynley.
- Dark Odyssey (1961)
- Dictionary of Sex (1964)
- Erotic Touch (1964)
- The Dirty Girls (1965)
- The Alley Cats (1966)
- Carmen, Baby (1967)
- Thérèse and Isabelle (1968)
- Camille 2000 (1969)
- The Lickerish Quartet (1970)
- Mother (1973)
- Score (1974)
- The Private Afternoons of Pamela Mann (1975)
- Naked Came the Stranger (1975)
- The Image (1975)
- The Opening of Misty Beethoven (1975)
- Barbara Broadcast (1977)
- Maraschino Cherry (1978)
- The Cat and the Canary (1979)
- World of Henry Paris (1981)
- The Tale of Tiffany Lust (1981)
- The Princess and the Call Girl (1984)
In 1977, Metzger's film The Opening of Misty Beethoven was the recipient of the first Adult Film Association of America awards for Best Direction (as Henry Paris), Best Film, and Best Actor (Jamie Gillis). In 2002 the same production won Best Classic Release on DVD.
In 2010, Metzger was also the recipient of a Lifetime Achievement Award from the Oldenburg International Film Festival, where he served as a judge in 2011. His work was the subject of a retrospective at the UCLA Film and Television Archive in the summer of 2011.
- A Talk with Radley Metzger (Interview)
- Cook, David A. (2002). History of the American cinema 9. University of California Press. pp. 274–275. ISBN 0-520-23265-8.
- Radley Metzger at the Internet Movie Database
- Dreams of desire - The Films of Radley Metzger by Nathaniel Thompson. Mondo-digital film magazine. Last retrieved June 6, 2007.
- Detailed Info on Work and Life (German)
- Gary Morris, Thoughts on Radley Metzger, May 1998 issue of Bright Lights film journal, Retrieved June 6, 2007
- Aaron Hillis, 2010 podcast interview with Radley Metzger, GreenCine Daily