Alexander B. H. Cox (born 15 December 1954) is an English film director, screenwriter, actor, non-fiction author and broadcaster. Cox experienced success early in his career with Repo Man (1984) and Sid and Nancy (1986). Since the release and commercial failure of Walker (1987), his career has moved towards independent films, including Highway Patrolman (1991) and Three Businessmen (1998), and microbudget features such as Searchers 2.0 (2007) and Repo Chick (2009).

Cox has taught screenwriting and film production at the University of Colorado, Boulder and has written numerous educational books on film and television.

Cox was born in Bebington, Merseyside, England in 1954. He attended Worcester College, Oxford, and later transferred to the University of Bristol, where he majored in film studies. Cox secured a Fulbright Scholarship, allowing him to study at the University of California, Los Angeles, United States, where he graduated from the School of Theater, Film and Television with an MFA.

Cox began reading law as an undergraduate at Oxford University, but left to study radio, film and TV at Bristol University, graduating in 1977. Seeing difficulties in the British film scene at the time, he first went to Los Angeles to attend film school at UCLA in 1977. There he produced his first film, Edge City (also known as Sleep Is for Sissies), a 40-minute surreal short about an artist struggling against society. After graduation, Cox formed Edge City Productions with two friends with the intention of producing low-budget feature films. He wrote a screenplay for Repo Man, which he hoped to produce for a budget of $70,000, and began seeking funding.

Michael Nesmith agreed to produce Repo Man, and convinced Universal Studios to back the project with a budget of over a million dollars. During the course of the film's production, the studio's management changed, and the new management had far less faith in the project. The initial cinema release was limited to Chicago, followed by Los Angeles, and was short-lived.

After the success of the soundtrack album (notable for featuring many popular LA punk bands), there was enough interest in the film to earn a re-release in a single cinema in New York City, but only after becoming available on video and cable. Nevertheless, it ran for 18 months, and eventually earned $4,000,000.

Continuing his fascination with punk music, Cox's next film was an independent feature shot in London and Los Angeles, following the career and death of bassist Sid Vicious and his girlfriend Nancy Spungen, initially titled Love Kills and later renamed Sid and Nancy. It was met warmly by critics and fans, though heavily criticised by some, including Pistols' frontman John Lydon, for its inaccuracies. The production of this film also sparked a relationship with Joe Strummer of the Clash, who would continue to collaborate with the director on his next two films.

Cox had long been interested in Nicaragua and the Sandinistas (both Repo Man and Edge City made references to Nicaragua and/or Latin American revolution), and visited in 1984. The following year, he hoped to shoot a concert film there featuring the Clash, the Pogues and Elvis Costello. When he could not get backing, he decided instead to write a film that they would all act in. The film became Straight to Hell. Collaborating with Dick Rude (who also co-starred beside Strummer, Sy Richardson and Courtney Love), he imagined the film as a spoof of the Spaghetti Western genre, filmed in Almería, Spain, where many classic Italian westerns were shot. Straight to Hell was widely panned critically, but successful in Japan and retains a cult following. On 1 June 2012, Cox wrote an article in The New York Times about his long-standing interest in spaghetti westerns.