Rapid industrialization results in the production of huge amounts of solid and/or liquid wastes, which is usually discharged into the nearby water bodies, leading to the damage of the important ecosystems and seafood products. Therefore, the present overview aims to highlight the issue of pollution of aquatic ecosystems and fish health. Heavy metals are widely used in every industrial application; therefore, they form the core group of pollutants of any industrial discharge. Some of the heavy metals such as Fe, Mn, Co, Ni, Cu, Zn and Cr are essential as they form the cofactor for many of the enzymes and also needed in metabolic activities. On the contrary, their exceeding amount is also detrimental to both animals and human beings. Based on the current review, it has been observed that to monitor the health of indicator organism (fish), battery of bioassays or biomarkers are required. In addition to this rationale of using the few selected parameters such as condition indices, bioaccumulation, blood biochemistry, marker enzymes of tissue damage, oxidative stress, genotoxicity and histopathology in describing, the aquatic pollution has also been emphasized. All these parameters are significantly affected by heavy metals and hence proved as useful tools in biomonitoring or toxicity assessment studies. Since fishes are consumed by large mass of population due to their high protein and polyunsaturated fatty acid content, human health is also under danger.