REUTERS/Fred Prouser
Roger Ailes, former chairman and CEO of Fox News and Fox Television Stations, answers questions during a panel discussion at the Television Critics Association summer press tour in Pasadena, California July 24, 2006.
Gibney is staying tight-lipped about the planned film.
"As a matter of course, I don't talk about what I'm working on," the director told the Hollywood Reporter, which broke news of the project.
According to the trade magazine, the Ailes documentary is in development and hasn't yet been placed with a network.
In July of last year, Ailes, 76, found himself embroiled in controversy after anchor Gretchen Carlson alleged that he sexually harassed her while working at the Fox News Channel. Many other women then came forward with similar allegations, including now-former FNC anchor Megyn Kelly. Ailes resigned from his position at the cable news channel later that same month.
In August, news surfaced that he was advising Donald Trump on his presidential campaign in advance of the aired debates.
Gibney, who has directed nearly 40 projects over his career, made a bigger name for himself in 2015 with the HBO documentary "Going Clear," inspired by the book about Scientology's beliefs and alleged abuses of the same name by Lawrence Wright. The movie went on to win three Emmys. Last year, Gibney told Business Insider that he was thinking about a "Going Clear" sequel.