Jeju may refer to:
- Jeju Island (Jejudo), an island of South Korea
- Jeju Province (formerly transliterated Cheju), a province of South Korea comprising Jejudo
- Jeju City, the biggest city on Jejudo
- Jeju dog, a dog native to Jejudo
- Jeju language, the Koreanic language spoken on Jejudo
- Jeju people
- Jeju Black, a cattle breed from the island
- Jeju horse
- Jeju Air, an airline operating from Jejudo
- Jeju Bank, the subsidiary of Shinhan Bank
- Jeju (woreda), one of the 180 woredas district in the Oromia Region of Ethiopia
- Jeju Shinhwa World, a fully integrated South Korean resort located on Jeju Island
- Hoplerythrinus unitaeniatus, an Amazonian fish known as jeju