Certain elements behave differently when their Particle size reduced to nano-level and exerts different impact on the exposed organisms. Such impact could be evaluated through animal models and safe materials can be suggested for various applications including pharmaceuticals. Subsequently create awareness among the public about its effect from the environment. In this study the biochemical assays ie molecular biomarker development ( Microsomal /Cytosolic fractions of Muscle ,Gill, Liver , Kidney of fish) were made against ZnO nanoparticles.The specific activity of antioxidant enzymes such as catalase(CAT) ,Superoxide dismutase (SOD) andGlutathione S transferase (GST) and Ethoxyresorufin o dealkylase (EROD) were also measured in response to ZnO nanoparticle on fish showed induction of toxic effects by defense enzyme activity. The level of antioxidant enzymes in liver showed significant decreases with increasing doses. Biochemical and Antioxidant enzymes responses in fish could be used as a biomarker for the early detection of nanoparticles exposure.