Haggai is one of the Biblical minor prophets.
Haggai or Hagai may also refer to:
- Book of Haggai, the book of the Bible attributed to the prophet Haggai
- Haggai, Missouri, ghost town, United States
- Beit Hagai, officially just Hagai, a religious Israeli settlement in the West Bank
- Hagai Levi, Israeli film and television director
- Hagai Shaham, Israeli violinist
- Hagai Zamir, Israeli paralympic champion
- Haggai Ndubuisi, Nigerian gridiron football player