Surname エイイチ (Eiichi 
, エイイチ , Eiiti 
) , in all the world, is a common family name. The family name エイイチ is habitual in Eastern Asia, particularly Japan, where it is quite a common surname, Taiwan, where it is quite a rare surname, and Hong Kong, where it is a rare surname. Not in comparison with a country's population, this name is the most popular in Eastern Asia, particularly Japan, Taiwan, and China. Much less frequently, エイイチ is the forename as well as the last name.