Yuzo Koshiro (古代祐三, Koshiro Yūzō, born December 12, 1967) is a Japanese composer and sound programmer. He is often regarded as one of the most influential innovators in chiptune and video game music, producing music in a number of genres including rock, jazz, symphonic, and various electronic genres such as house, electro, techno, trance, and hip hop.

Koshiro and his sister Ayano founded the game development company Ancient in 1990, of which he remains the president. He has been cited as creating some of the most memorable game music of the 1980s and 1990s contributing for games such as Nihon Falcom's Dragon Slayer and Ys series, as well as Sega's The Revenge of Shinobi and Streets of Rage series. The soundtracks for the latter have been cited by some to be ahead of their time.