| Named By: | Hu, Y & Wang, Y. in 2002 |
| Time Period: | Early Cretaceous |
| Location: | China, Liaoning Province - Yixian Formation |
| Size: | 35 centimetres long |
| Diet: | Herbivore |
| Fossil(s): | Several specimens, some quite complete |
| Classification: | | Chordata | Mammalia | Multituberculata | Plagiaulacida | Eobaataridae | |
Sinobaatar is a genus of extinct mammal from the Lower Cretaceous of China. It is categorized within the also extinct order Multituberculata and among these it belongs to the plagiaulacid lineage (a possible infraorder). Sinobaatar was a small herbivore during the Mesozoic era, commonly called "the age of the dinosaurs". The genus was named by Hu Y. and Wang Y. in 2002. Three species have been described.
It has been found in Lower Cretaceous strata of the Yixian Formation in Liaoning, China. According to Hu & Wang (2002),
"[t]he dental features of Sinobaatar show again that eobaatarids are obviously intermediate between Late Jurassic multituberculates and the later forms".
Many Multituberculata are only known from teeth, but the type specimen of Sinobataar is a reasonably complete skeleton.
Sinobataar was eaten, at least on occasion, by the feathered dinosaur Sinosauropteryx prima (Hurum et al. 2006).