Justin Marks (born April 27, 1980) is an American screenwriter, producer and television showrunner. He is best known for writing Disney's live-action remake of The Jungle Book, co-writing Top Gun: Maverick, and for creating and showrunning the Starz espionage thriller Counterpart.

One of the first scripts he penned was Street Fighter: The Legend of Chun Li for 20th Century Fox. A year prior, he had written a script for a potential He-Man film. Initially entitled Grayskull: The Masters of The Universe, the script was praised by fans yet was never used since the script was rewritten, with the film still being in development hell.