Educated by the Salesians although his family was not Roman Catholic, Boorman first began by working as a dry-cleaner and journalist in the late 1950s and then he moved into TV documentary filmmaking, eventually becoming the head of the BBC's Bristol-based Documentary Unit in 1962. Capturing the interest of producer David Deutsch, he was offered to direct a film aimed a repeating the success of A Hard Day's Night (directed by Richard Lester in 1964): Catch Us If You Can (1965) is about competing pop group Dave Clark Five. While not as successful commercially as Lester's film, it smoothed Boorman's way into the film industry. Boorman was drawn to Hollywood for the opportunity to make larger-scale cinema and in Point Blank (1967), a powerful interpretation of a Richard Stark novel, brought a stranger's vision to the decaying fortress of Alcatraz and the proto-hippy world of San Francisco. Lee Marvin gave the then-unknown director his full support, telling MGM he deferred all his approvals on the project to Boorman.

After Point Blank, Boorman re-teamed with Marvin (and Toshiro Mifune) for the robinsonade of Hell in the Pacific (1968), which tells a fable story of two representative soldiers stranded together on an island and forced to put aside war to survive.

Returning to the UK, he made Leo The Last (US/UK, 1970). This film exhibited the influence of Federico Fellini and even starred Fellini regular Marcello Mastroianni, and won him a Best Director award at Cannes.

Boorman achieved much greater resonance with Deliverance (US, 1972, adapted from a novel by James Dickey). The odyssey of city people played by Jon Voight, Burt Reynolds, Ronny Cox and Ned Beatty as they trespass into Appalachian backwoods and discover their inner savagery, captured the imagination of audiences and became Boorman's first true box office success earning him an Academy Award nomination.

At the beginning of the 1970s Boorman was planning to film The Lord of the Rings and corresponded about his plans with the author, J. R. R. Tolkien. Ultimately the production proved too costly though some elements and themes can be seen in Excalibur.

A wide variety of films followed: Zardoz (1974) starred Sean Connery in a bizarre take on post-apocalyptic science fiction. Zardoz is a film that provokes a wide variety of responses, from those that regard it as an unsung masterpiece to those that laugh at its frequent pretensions. Boorman was selected as director for Exorcist II: The Heretic (1977), but the resultant film was widely ridiculed and regarded as a total failure.

Excalibur (UK, 1981), was a long held dream project of Boorman's, is well-remembered as a mythical film and one of the very few "true" retellings of the Arthurian legend and tragedy. Boorman cast actors Nicol Williamson and (now Dame) Helen Mirren against their protests as the two disliked each other intensely, but Boorman felt their mutual antagonism would enhance their characterizations of the characters they were playing. The production was based in the Republic of Ireland where Boorman had re-located. For the film he employed all of his children as actors and crew and several of Boorman's later films have been 'family business' productions.

Hope and Glory (1987, UK) is his most autobiographical movie to date, a re-telling of his childhood in London during The Blitz. Produced by Goldcrest Films with Hollywood financing the film proved a Box Office hit in the US earning another Oscar nomination for Boorman as Director and swept the board at that years BAFTA's. However his 1990 US produced comedy about a dysfunctional family Where the Heart Is was a major flop.

Very eco-conscious, Boorman's foray into Hollywood filmmaking, The Emerald Forest (1985), a rainforest adventure, casts his actor son Charley Boorman as an eco-warrior, mingling commercially-required elements - action and near-nudity - with anthropological detail and the gorgeous threat of a green inferno (the film was adapted into a book of the same name by award winning author Robert Holdstock). When his friend David Lean died in 1991 Boorman was announced to be taking over direction of Lean's long planned adaptation of Nostromo though the production collapsed.Beyond Rangoon (US, 1995) and The Tailor of Panama (US/Ireland, 2000) both explore unique worlds with alien characters stranded and desperate in them.

In 1999, Boorman won the "Best Director" award at the Cannes Film Festival for his black-and-white biopic of Martin Cahill (The General), a somewhat glamorous yet mysterious criminal in Ireland who was killed, apparently by the Irish Republican Army.

He lives in Annamoe, County Wicklow, Republic of Ireland, close to the famous Glendalough twin lakes with his wife, the former Christel Kruse. He has four children, Charley, Daisy, Katrine and Telsche Boorman. Charley Boorman has managed a career as an actor in films not directed by his father. Telsche Boorman who wrote the screen play for Where the Heart Is died of cancer in 1997.