Iwai (written: lit. "rock well" or ) is a Japanese surname. Notable people with the surname include:
, Japanese trade union leader , Japanese footballer , Japanese politician , Japanese musician Iwai Hanshirō I (1652–1699), Japanese kabuki artist Iwai Hanshirō V (1776–1847), Japanese kabuki artist Iwai Hanshirō VIII (1829–1882), Japanese kabuki artist , Japanese economist , Japanese curler , Japanese politician , Japanese film director , Japanese footballer , Japanese artist , Japanese voice actress , Japanese pop singer
Fictional characters , a Confidant and supporting character in Persona 5 and Persona 5: The Phantom X