Shirō Hamaguchi (浜口 史郎, Hamaguchi Shirō, born November 19, 1969) is a Japanese anime composer, arranger and orchestrator. He is best known for composing music to the anime franchises One Piece and Oh My Goddess! and arranging/orchestrating music in the Final Fantasy series. He frequently collaborates with fellow composers Kohei Tanaka and Akifumi Tada on anime scores.