Seiji Yokoyama (横山 菁児, Yokoyama Seiji, March 17, 1935 – July 8, 2017) was a prolific Japanese incidental music composer from Hiroshima who was best known to the West for his work on the Space Pirate Captain Harlock and Saint Seiya series. He was a graduate student of Kunitachi College of Music.He made his debut as a composer for the ending theme of The Adventures of Hutch the Honeybee in 1971. He was known for his symphonic sound for many television programs.