Otto Nüsslin (26 October 1850, Karlsruhe – 2 January 1915), Baden-Baden) was a German zoologist and forester. After completing his studies, he joined the staff of Bernard Altum (1824-1900) and Robert Hartig (1839-1901) at the Forestry Academy in Eberswalde. In 1880 Nüsslin founded the Lehrstuhl für Zoologie und Forstzoologie (Department of Zoology and Forest Zoology) at the Karlsruhe Institute of Technology, where he served as a professor until 1914. Several species bear his name, such as: Henneguya nuesslini, Adelges nuesslini, Bursaphelenchus nuesslini and Kissophagus nuesslini.