Robert Mandel was born in Oakland, California, but grew up in Queens, New York, where he became interested in theater. Mandel attended the Bucknell University and decided to pursue stage directing at the Manhattan Theatre Club and the The Public Theatre during the early 1970s.
During the late 1970s, Mandel attended M.F.A. studies at Columbia University and then at the AFI Conservatory, where he graduated in 1979. During his studies at the American Film Institute, Mandel received the Alfred Hitchcock Award for his thesis film, Night at O'Rears, which then went on to win the First Prize at Filmex in Los Angeles, First Prize at the USA Film Festival in Dallas, Texas; and was exhibited at the New York Film Festival at Lincoln Center.
Mandent went on to become a successful film director, as well as a television series director, having directed Lost, Nash Bridges and The Practice. He was the director of the pilot for The X-Files and the sixth episode of Prison Break.
Mandel is currently the dean of AFI Conservatory. He is the first alumnus of the program to be selected a dean.