Stephen Percy Harris (born 12 March 1956) is an English musician and songwriter, best known as the bassist, keyboardist, backing vocalist, primary songwriter, founder, and leader of heavy metal band Iron Maiden. He is the band's only constant member since their inception in 1975 and, along with guitarist Dave Murray, the only member to appear on every album.

Harris has a recognisable and popular style of bass playing, particularly the "gallop" which can be found on many Iron Maiden recordings, such as the singles "Run to the Hills" and "The Trooper". In addition to his role as the band's bass player, writer and backing vocalist, he has undertaken many other roles for the group, such as producing and co-producing their albums, directing and editing their live videos and performing studio keyboards and synthesizers. He has been cited as one of the greatest heavy metal bassists ever.

In 2012, Harris released his debut solo album, British Lion, which was followed by The Burning in 2020.