John Knoll (born October 6, 1962) is an American visual effects supervisor and chief creative officer (CCO) at Industrial Light & Magic (ILM). One of the original creators of Adobe Photoshop (along with his brother, Thomas Knoll), he has also worked as visual effects supervisor on the Star Wars prequels and the 1997 special editions of the original trilogy. He also served as ILM's visual effects supervisor for Star Trek Generations and Star Trek: First Contact, as well as the Pirates of the Caribbean series. Along with Hal Hickel, Charles Gibson and Allen Hall, Knoll and the trio's work on Pirates of the Caribbean: Dead Man's Chest earned them the Academy Award for Best Visual Effects.

Knoll has been praised by directors James Cameron, Gore Verbinski, Guillermo del Toro, and Brad Bird. Del Toro, who worked with Knoll for the first time on Pacific Rim, stated "He basically has the heart of a kid and the mind of a scientist, and that's a great combination."

Knoll is also the inventor of Knoll Light Factory, a lens flare generating software inspired by his work at Industrial Light and Magic.