Water pollution is significant only when it influences living or biological systems either directly or indirectly. In a broad sense, it can be depicted as a normal consequence of the growth of organisms including man in or near the aquatic habitat. The presence of toxic pollutants in aquatic ecosystems poses a serious threat to environmental health. Industrialization and growth of human population have led to a progressive deterioration in the quality of the earth's environment. These harmful chemicals/xenobiotics are harming the aquatic ecosystem involving flora and fauna of the water bodies. The present study is thus investigating the effect of different types of phenolic compounds on biochemical parameters and enzymes involved in metabolic pathways of Clarias batrachus, a fresh water fish. The present study reveals the disaster and lethargic effect of phenolic compounds on the metabolic and physical parameters of C. batrachus. The calculated LC50 value for phenol and m-cresol exposure in C. batrachus over periods of up to 96 hours is 28.45 mg l-1 and 25.7 mg l-1 respectively. The studies showed that in fishes after exposure to phenolic compounds (treated group), there was a significant decreased level of serum cortisol, total carbohydrate concentration, blood glucose concentration, pyruvate concentration and different enzymes studied which are associated with the normal functioning of metabolic organs at P<0.05 in comparison to normal (untreated group).