Otto Sverdrup Engelschiøn (30 October 1902 – 8 May 1982) was a Norwegian marketer, businessperson, resistance member and genealogist. He was born in Kristiania as a son of consul-general Søren Dass Brodtkorb Sverdrup Engelschiøn (1867–1909) and Janka Hansen (1869–1935). In 1928 he married Gudrun Irgens Garmann. Engelschiøn chaired the Norwegian Genealogical Society from 1957 to 1968, and thereafter served as deputy chairman. He was also a bibliophile, chairing twice as well as the contest jury for the Most Beautiful Book of the Year. Engelschiøn also issued a crime novel under a pseudonym.