Kenji Ito became interested in music at the age of 4. By the time he began composing at the age of 10, he had learned to play alto saxophone, clarinet, and piano. In March of 1990, he was recruited by Square to compose music together with Nobuo Uematsu for the Game Boy title, Final Fantasy Legend II. Shortly after in 1991, he composed the complete soundtrack for Final Fantasy Adventure, another Game Boy title. Beginning in 1992, Ito began composing music for the Romancing SaGa trilogy. He also arranged Uematsu's famous Final Fantasy tunes for the garish Chocobo Racing soundtrack.
Ito left Square in 2001 to become a freelance composer, shortly thereafter composing his magnum opus for the Dreamcast title Culdcept II along with various other works for Dark Chronicle Premium Arrange and Shadow Hearts II.
In 2002, Ito announced that he'd received work from Square again, updating his compositions for remakes Sword of Mana and Romancing SaGaRomancing Saga: Minstrel Song, while churning out new tunes for Children of Mana and Dawn of Mana.
In 2005 Ito joined Harmonics International as a musician to perform in concerts and record music. In more recent years he contributed to the Deathsmiles - Arrange Album and scored Devil Survivor 2.