Hansen
The taxon authority Hansen may refer to:
- Alfred Hansen (1925–2008, A.Hansen), botanist
- Aslak Kappel Hansen, entomologist
- Bent Hansen, Danish zoologist
- Bertel Hansen, botanist
- Bruce Frederick Hansen (born 1944, B.F.Hansen), botanist
- Carlo Hansen (1932–1991, C.Hansen), botanist
- Dean Cyrus Hansen, U.S. entomologist
- Eric Steen Hansen (born 1943, E.S.Hansen), botanist
- Gerhard Armauer Hansen (1841–1912), botanist
- Hans Jacob Hansen (1855–1936), zoologist
- Hans Nicholas Hansen, Danish-American mycologist and phytopathologist
- Hans Vilhelm Hansen (born 1951, H.V.Hansen), botanist
- Jesper Guldberg Hansen, cnidariologist
- Louis A. Hansen, biologist
- Michael Hansen (1956–2000), coleopterologist
- Niels Ebbesen Hansen (1866–1950, N.E.Hansen), botanist
- Ove Juel Hansen (born 1945, O.J.Hansen), botanist
- Poul Arne Hansen (1902–1972), Danish-American bacteriologist
- Richard Maas Hansen (born 1924), mammalogist
- Thomas Hansen, paleontologist
- Victor Hansen (1889–1974), Danish entomologist