Karl Harald Adolf Haanshus (December 26, 1860 – January 3, 1936) was a Norwegian physician and entomologist. He joined the Norwegian Entomological Society in 1915. He was its vice chairman from 1933 to 1935, and he was also a member of the editorial committee of the Norwegian Journal of Entomology. Haanshus was born in Kristiania (now Oslo). He received a medical degree in 1888 and practiced for 10 years as a town physician in Fredrikstad. He then moved back to Kristiania, where he worked as a pediatrician until his death on January 3, 1936.