Masako Otsuka (大塚 正子, Ōtsuka Masako) is a Japanese music composer and performer. Not much is publicly known about her, but many of her compositions tend to use traditional stringed instruments. She has composed music for Koei since 2007.

For her work in Harukanaru Toki no Naka de 5, Otsuka wanted to capture the game's setting by making compositions that used the stringed instruments of both cultures. She wanted to make the game's music replicate a dramatic period piece or a movie soundtrack by composing several variants of the same song; by doing so, she believes a song can play in layers and act as a pivotal component for the tempo of a scene. Her hardest compositions to create were the game's love themes since romantic music isn't her forte. The audio construction for this game was the first time she felt the pressures of being a sound director.

Works for KoeiEdit

Otsuka has been credited for composing or arranging music tracks for the following titles.