Otto Emanuel Andersson (27 April 1879 – 27 December 1969) was a Finnish musicologist.
Andersson studied first at the Helsingfors musikinstitut (now the Sibelius Academy), becoming a teacher there. He studied folklore and music from 1908 onwards, and gained his Ph.D. in 1923 at the University of Helsinki. From 1926 on he held the Robert Mattsons chair in musicology and folklore at the Åbo Akademi. In 1906 he formed the Brage Society, dedicated to Finland’s Swedish folk music and culture, serving later as the group's chairman and choirmaster.
Andersson founded the three music magazines, wrote a variety of valuable essays and collected and arranged traditional Swedish, Finnish and Estonian folk songs and dances. He also served as a contributor to the Svensk uppslagsbok dictionary, producing music-related entries.