Otto Olsson (19 December 1879 – 1 September 1964) was a Swedish composer of classical music. Otto Olsson was one of the greatest organ virtuosos of his time. He studied organ with Lagergren and composition with Dente at the Royal Swedish Academy of Music, and then joined the faculty there, where he taught harmony (1908-24) and then organ (1924-45). He was also the organist at the Gustav Vasa church in Stockholm. He became a member of the Swedish Royal Academy of Music in 1915.