Real name: 横山菁児

Effective period / Period of releases: 1971 - 2022

Seiji Yokoyama (born March 17, 1935, Hiroshima, Japan - died July 8, 2017, Sera, Hiroshima, Japan) was a Japanese soundtrack music composer, perhaps best known for his work on the anime television series Space Pirate Captain Harlock (1977-1979) and Saint Seiya (1986-1990).

In 1957, he graduated as a composer from the Kunitachi Music School in Japan. He composed music for Japanese television, radio and movies. For his compositions he mainly used traditional instruments like piano, violins, etc, along with more modern instruments like drums and electric guitar, resulting in a very particular and unique style.