Family members said Stuart died of cancer Thursday night at his home in Los Angeles.
The award-winning filmmaker primarily directed documentaries, but he's probably best known for the "Willy Wonka" film, starring Gene Wilder.
During the 1960s and 1970s, Stuart and David L. Wolper established a base of West Coast documentary production at a time when New York filmmakers and TV network news dominated the field.
Stuart's documentary films include three editions of "The Making of the President" and "American Masters."
The Associated Press contributed to this report.