Limusaurus is a genus of dinosaur belonging to the group Elaphrosaurinae. It lived during the Late Jurassic period, approximately 161 to 145 million years ago. The first fossils of Limusaurus were discovered in the Shishugou Formation of Xinjiang, China.

Limusaurus was a diminutive and slender creature. Initially considered an adult based on the level of bone fusion, the holotype was later reevaluated as a subadult when compared to other specimens. Its estimated length is about 1.7 m (5 ft 7 in), with an approximate weight of 15 kg (33 lb). Another adult specimen is believed to have been 15% larger than the holotype. Consequently, the adult Limusaurus was still relatively small, measuring around 6 to 8 feet (2 to 2.5 meters) in length. As a member of the oviraptorosaurian group, it displayed distinctive traits that distinguished it from other dinosaurs.

One of the most remarkable characteristics of Limusaurus is its unique feeding behavior. Juvenile Limusaurus had sharp teeth and evidence of a carnivorous diet, while adult Limusaurus displayed a distinct shift towards herbivory, with evidence of a beak-like structure replacing their sharp teeth.

Additionally, Limusaurus had a toothless premaxilla, indicating its advanced adaptation to herbivorous feeding as it matured.

Limusaurus is not only the first definite ceratosaur discovered in Asia but also one of the earliest members of this group, thriving during the Oxfordian stage of the Jurassic period, approximately 161-157 million years ago. Xu and colleagues' findings suggest that the Asian dinosaur fauna during the Middle to Late Jurassic might have been less regionally restricted than previously assumed, hinting at the possibility of a land connection between Asia and other continents at that time. In a 2014 conference abstract, biologist Josef Stiegler and colleagues reported that Limusaurus holds the distinction of being the earliest known toothless theropod and the sole non-bird theropod to exhibit robust bilateral reduction of its digits, with the outer fingers reduced in size.