A total of 75 species of fishes belonging to 54 genera, 26 families and 10 orders has been recorded from the Poma River of Arunachal Pradesh and Assam. The order cypriniformes represented highest diversity with 40 species (53%), followed by Siluriformes with 16 species (21%), Anabantiformes with 9 species (12%), Synbranchiformes with 3 species (4%) and Perciformes with 2 species. Anguilliformes, Beloniformes, Gobiiformes and Cichliformes were very rarely seen in the study area represented by a single species each along with an exotic fish (Oncorhynchus mykiss) under order Salmoniformes. The fish fauna of Poma River is a mixture of endemic hill stream, threatened, exotic and widely distributed forms and consists of 3 Endangered (EN), 5 Near Threatened (NT), 3 Vulnerable (VU), 6 Data Deficient (DD) and 49 Least Concerned (LC) categories of IUCN. Nine species were not evaluated. In the present study a new species was also described, and assigned with the name Channa pomanensis referring to the type locality, Poma river.