August Busck (February 18, 1870, Randers, Denmark – March 7, 1944, Washington, D.C., U.S.A.) was a Danish entomologist who became an American citizen.
Busck was an employee of the Bureau of Entomology within USDA.
He is best known for his work with microlepidoptera, of which he described over 600 species.
His collections of Lepidoptera from North America and the Panama Canal Zone are held by the National Museum of Natural History in Washington, D.C.