Viking Dahl, (8 October 1895 - 5 January 1945), was a Swedish composer, active also as a painter and an author. He was brother to K. G. William Dahl.
Viking Dahl was born in Osby in Scania and studied at the Royal College of Music 1915-1919 in Stockholm and thereafter in Copenhagen and Berlin. During a stay in Paris 1920, he wrote the dance drama Maison de Fous for Ballets Suédois.
He developed his own avant-gardism during his studies in Stockholm, and in Paris he met the radical French composers of the time, among them Darius Milhaud and Maurice Ravel. When he returned to Sweden he became an organist in Varberg, where he lived until his death.