In 1979 and 1980, two specimens were discovered of a small herbivorous dinosaur during excavations near Dashanpu in Sichuan. In 1983 Dong Zhiming and Tang Zilu named the fossils under the type species Xiaosaurus dashanpensis. The generic name is derived from Chinese xiáo, 曉, "dawn", a reference to the age of the fossil. The specific name refers to Danshanpu.[1] In 1992 Peng Guangzhao renamed Agilisaurus multidens He & Cai 1983 (now Hexinlusaurus) into a second species of Xiaosaurus: Xiaosaurus multidens,[2] but this has not been accepted.