Water pollution is a matter of great concern in lentic and lotic ecosystems. Generally water pollutants like heavy metals, organic compounds, etc. generate from industries and domestic activities. All of these pose serious threat to the fish population in freshwater as well as marine water bodies. An impact caused by water pollutants especially genotoxins depend not only upon its concentration, but also on the duration (acute and chronic exposure) and showed individual and/or combination of pollutants or genotoxins. Genotoxicity of fish with special reference to micronucleus induction in the erythrocytes of fish is an easy screening of water pollution. The present review deals with past and present research works of major water pollutants discharge and their impact on several fish species from available literatures.