Jack-in-the-Box (also Jack in the Box) may refer to:
- Jack-in-the-box (origin of the phrase), a wind-up toy featuring an object that pops out from a box when wound
- Jack-in-the-Box, a superhero character from the Astro City comic book series
- Jack-in-the-box (composition), a musical composition by Erik Satie
- Jack in the Box, an American fast-food restaurant chain
- the Jack-in-the-Box Effect, an effect caused by ammunition detonating inside a tank
