Erliansaurus (meaning "Erlian lizard") is a genus of therizinosaur theropod dinosaur that lived in Asia during the Cenomanian stage of the Late Cretaceous period in what is now Nei Mongol, Iren Dabasu Formation.

The type species, Erliansaurus bellamanus, was described by Xu Xing, Zhang Xiaohong, Paul Sereno, Zhao Xijin, Kuang Xuewen, Han Jun and Tan Lin in 2002.

[1] The holotype, LH V0002, was uncovered in the Iren Dabasu Formation dating from the Cenomanian stage.

[1] The holotype specimen represents a not fully-grown individual based on one unfused caudal vertebra, and therefore its adult size may be larger than the contemporary Neimongosaurus.

[1] It was a small to medium-sized therizinosaur with an estimated length from 2.6 to 4 m (8.5 to 13.1 ft) and a weight of 91 to 400 kg (201 to 882 lb).