Isogai (written: 磯貝, 磯谷 or 礒貝) is a Japanese surname. Notable people with the surname include:
, Japanese judoka , Japanese footballer , Japanese general , Japanese singer and musician , Japanese sport wrestler
Fictional characters , a character in the manga series Assassination Classroom , a character in the anime series Little Battlers Experience WARS
See also 8251 Isogai, a Mars-crossing asteroid