Overa- Aru harbours a good faunal assemblage. It is home of many common, rare and endangered faunal species. Some important species present there include the hangul (Cervus hangulu), musk deer (Moschus cupreus), serow (Capricornis sumatraesis), Rhesus macaque (Macaca mulata), Kashmir grey langur (Semnopithecus ajax), leopard (Panthera pardus) and the leopard cat (Felis bengalensis). The rare and endangered hangul deer is one of the prime animals of this reserve though their numbers are low. Other animal species found in the sanctuary include red fox (Vulpus vulpes) and Himalayan black bear (Ursus thibetanus). The brown bear (Ursus arctos) also shares this divine terrain and may make an unexpected appearance. The leopard is a prominent carnivore in Overa-Aru.