John Frederick Milius is an American filmmaker. He was one of the writers for the first two Dirty Harry films, received an Academy Award nomination as screenwriter of Apocalypse Now, and wrote and directed The Wind and the Lion, Conan the Barbarian and Red Dawn.

He wrote a number of iconic film lines such as "Charlie don't surf" and "I love the smell of napalm in the morning," from Apocalypse Now, and the famous Dirty Harry one-liners delivered by Clint Eastwood, including "Go ahead, make my day" and "Ask yourself one question, 'do I feel lucky?' Well, do you, punk?". Milius also wrote the USS Indianapolis monologue in the film Jaws; the sequence performed by Robert Shaw. After his work on Rough Riders (1997), Milius became an instrumental force in lobbying Congress to award President Theodore Roosevelt the Medal of Honor (posthumously), for acts of conspicuous gallantry while in combat on San Juan Hill. Milius made two films featuring Roosevelt: The Wind and the Lion (where he was played by Brian Keith) and the made-for-TV film Rough Riders (where Tom Berenger took the role).