The Chambal River is an important river in the Ganges river system. The Chambal River was declared as a National Chambal Sanctuary with an aim to provide fully protected habitat for the conservation and propagation of highly endangered crocodilian species and other aquatic animals. The study area was comprised of a 395 km of the National Chambal Sanctuary, from Pali to Chakarnagar. In the present study 46 species of fishes belonging to 16 families were observed during the course of present study and there is a general observation suggesting rapid decline in fish population due to large-scale illegal fishing. Two species of Crocodiles, the Gharial (Gavialis gangeticus) and Mugger (Crocodylus palustris) and seven species of freshwater turtles (Pangshura tentoria, Kachuga dhongoka, Batagur kachuga, Hardell thurjii, Aspideretes gangeticus, Lissemys -punctata anderoni,) were identified in the study area. The major human activities that destroyed the habitat in the Chambal River are inthe form of extensive untraditional cultivation practices on the riverbanks, overgrazing, wood collection from riverside vegetation and sand mining. Sand Banks are very much useful for the aquatic animals