Karl Hoffmann (December 7, 1823 – May 11, 1859) was a German physician and naturalist.
Hoffmann was born in Stettin and studied at Berlin University. In 1853 he travelled to Costa Rica with Alexander von Frantzius to collect natural history specimens. He served as a doctor in the Costa Rican army during the invasion of William Walker in 1856. He died of typhoid in Puntarenas.
Hoffmann is commemorated in the names of a number of animals, including Hoffmann's Two-toed Sloth, Hoffmann's Woodpecker Melanerpes hoffmannii, the Sulphur-winged Parakeet Pyrrhura hoffmanni and a millipede Chondrodesmus hoffmanni (Peters, 1864).