Genus: Sinornithoides RUSSELL & DONG, 1993
Etymology: Latin, sino-, "China." The generic name is in allusion to the Chinese occurrence of a Saurornithoides-like dinosaur.

Species: youngi RUSSELL & DONG, 1993
Etymology: In honour of Chung-Chien Young (Yang Zhong Jian) for the number and breadth of his contributions to our understanding of the fossil reptiles of China.

Holotype: IVPP V9612

Locality: Exposures of cross-bedded red sandstone 0.7 km west of Muhuaxiao Village (39’36”N, 108’41”E). The village is in turn 4.1 km west of the town of Duguijiahan, Inner Mongolia (Nei Mongolia), China.

Horizon: Ejinhoroqi Formation.

Biostratigraphy:

Age: Late Early Cretaceous.

Material: Complete skull and skeleton of a juvenile.

Note: Has a furcula.
Note: Paleopathology, left metatarsal I has a bony callosity at mid length.

AZUMA, 2005

FPDM-V7218, V7219: Cast of skeleton.