Reidar Omang (26 November 1897 – 15 October 1964) was a Norwegian historian, librarian and archivist.
His father, Simen Oscar Fredrik Omang (1867-1953), was a noted botanist.
[3] During the Nazi occupation of Norway, he led the evacuation of documents from the Foreign Ministry archives to Sweden.
After the war, Reidar Omang published the two volume series Norsk utenrikstjeneste from 1955 to 1959.
Reidar Omang was a member of the Norwegian Academy of Science and Letters from 1957.