Composer, Orchestrator, and Pianist, Mariko Horikawa was born in Tokyo, Japan. Influenced by her parents, Mariko started playing the piano at the age of two. Mariko's career as a pianist, she won a first prize in the State Competition in the U.S. at the age of nine. After she came back from the U.S., she auditioned for Japan Piano Teachers Association(JPTA) and became a member. She entered Keio University