Robert Greenwald (born August 28, 1945) is an American film director, film producer, and political activist, noted in the 2000s for his documentaries critical of Fox News and of the George W. Bush administration, as well as numerous award-winning television movies from the 1980s and 1990s.

Greenwald was born and raised in New York City, the son of Harold and Ruth Greenwald. He attended the city's High School of Performing Arts. He was active in New York theater, directing the plays Me And Bessie (1975) and I Have a Dream (1976).

Greenwald then moved to Los Angeles, where he launched a successful career as a director for television.