Anzai (written: 安西, 安斎 or 安済) is a Japanese surname. Notable people with the surname include:
- Atsuko Anzai (安西 篤子, born 1927), Japanese novelist
- Chika Anzai (安済 知佳, born 1990), Japanese voice actress
- Earl I. Anzai (born 1941), American lawyer and politician
- Emma Anzai, Australian musician
- Hiroko Anzai (安西 ひろこ, born 1979), Japanese actress, model and gravure idol
- Fuyue Anzai (安西 冬衛, 1898–1965), Japanese poet
- Maria Anzai (安西 マリア, 1953–2014), Japanese idol
- Nobuaki Anzai (安斎 伸彰, born 1985), Japanese Go player
- Nobuyuki Anzai (安西 信行, born 1972), Japanese manga artist
- Shigeo Anzai (安斎 重男, born 1939), Japanese photographer
- Tatsuya Anzai (安在 達弥, born 1996), Japanese footballer
- Yukari Anzai (安齋 由香里, born 1995), Japanese-Taiwanese voice actress