A systematic survey of Rapti River was conducted once in a month for a period of one year from August 2018 to July 2019 from ten collection sites of Shravasti and Balrampur districts. Its main aim was to find out ichthyofaunal diversity and their conservation status. The results of the present study revealed the occurrence of 46 species belonging to 30 genera 19 families and 9 orders. The family Cyprinidae were dominated by 13 species followed by Bagridae (6 species); Ophiocephalidae (...) (4 species); Siluridae (3 species); Schileidae, Clariidae, Gobiidae, Notopteridae and Mastacembeleidae each with two species; Saccobranchidae, Chacidae, Ophiocephalidae, Gobiidae, Anabantidae, Nandidae, Osphronemidae, Ambassidae, Clupeidae, Eugraulidae, Belonidae and Tetradontidae each with one species. The fishes in these areas are under threat due to anthropogenic activities such as overfishing and pollution hence authors strongly recommend practical conservation action plan to prevent the species from extinction. (shrink)