The name "Jack" may refer to:
- JACK, a game by NepetaLast (t∣b∣c)
- Jack Rabbit, the main character of JACK.
- Jack (Animal Crossing) - The mystical Halloween spirit from the Animal Crossing series.
- Jack (Boss) - A boss from Mario: Rise Of Shadow.
- Jack (Pokémon TSD) - A Gym Leader in the show Pokémon TSD.
- The Jack series.
- Jack Johnson - The main character of the Jack series.
- Jack (Glitch) - The main character of the Glitch series.
- Jack (ZL) - A minor character in the Zaxinian Lifts.