Northeastern India, one of the Ichthyofaunal hot spot areas of our country, is marked by the presence of varied freshwater fishes,a few adapted to torrential waterflow. River Dhansiri is an important river of Dimapur District of Nagaland, India, which flows through Nagaland –Assam border harbouring rich aquatic flora and fauna. Very little studies have been carried out to document the fish biodiversity of the Dhansiri river till date. In the present study an attempt has been made to access the piscine diversity of this river. The survey results in finding of species of 34 fishes belonging to five (5) orders, thirteen (13) families and twenty four (24) genera. Cyprniformes is the dominant order while Osteoglossiformes is the least common.