George Henry Horn (April 7, 1840 – November 24, 1897) was an American entomologist who specialized in the study of beetles.

[1] He bequeathed his collections of insects to the American Entomological Society;[1] they are now in the Museum of Comparative Zoology at Harvard University.

[2] Most of Horn's work was written from a "monographic, systematic standpoint", and included an abundance of comparative analyses between different orders, suborders, and families of beetle.

[5] According to the entomologist Neal Evenhuis, Horn's taxonomy was almost beyond reproach, and this was no doubt due to careful and deliberate study of specimens while comparing them to types.

Horn made it a point to travel to European museums, attend foreign entomological society meetings, and study type material firsthand.