Various researches were performed on the fishes along the course of river Jhelum, Kashmir, India. The study shows that the concentration of heavy metals varied significantly among fish species, seasons, sites and organs. The concentration of pH, NO₃-N, Total Dissolved Solids, BOD and COD recorded increasing values towards the downstream sections of the river whereas DO, Ca and alkalinity recorded decreasing values towards the downstream areas of the river. This change in water quality results in un-even distribution and diversity of fishes. Apparently, the fishery resource of the River Jhelum has thus declined over a period of time indicating some stress or abnormal external influences which are altering the health of this vital economic-ecologic lotic water body.