Eijiro Kai graduated from Tokyo University of the Arts and obtained a Master's degree at the same university. He studied in New York and Bologna. Kai made his Wiener Staatsoper debut in 2003 and performed as Marcello, Lescaut, Sharpless, Belcore, and Enrico, among others. He is also active in concert appearances which include Messiah, Beethoven's Symphony No.9, Mša Glagolskaja and Ein Deutsches Requiem. He is a member of Nikikai.