Erlikosaurus is a genus of dinosaur from the Late Cretaceous Period about 80 mya. Its fossils were discovered in the Bayan Shireh Formation of Mongolia. The type species E. andrewsi was described by Altangerel Perle in 1980. Its name is derived from the demon Erlik from Mongolian mythology and the species E. andrewsi is named after paleontologist Roy Chapman Andrews. At the time it was the only known therizinosaur (then called segnosaurs). The discovery of its skull helped shed light on poorly known facts of the genus.
Erlikosaurus belonged to an odd group of theropods that ate plants instead of meat, and had a backward facing pubic bone. The jaws were tipped with a bony beak useful for eating tough plant matter. Scientists now know that many therizinosaurs were feathered, so it is likely that Erlikosaurus was, too. The feet had long, slender claws. The purpose for this is unclear. Although only a few fragments of fossils have been found, it is estimated that the adult had a length of 20 feet.