The present study was undertaken to assess the effect of organo phosphorous pesticide Chlorpyrifos, Cypermethrine and Endosulfan on the non target organisms of the fish Labeo Rohita for the following reasons. In India, the demand for the pesticides sold under various brand names has gone up from 1400 metric tones to 7500 metric tones in 1995 to 2005. The aquaculture forms that are being set up recently, in this region are suffering from the invasion of pesticides used in high quantities for agricultural practices. In India labeo rohita fish is one of the majar carps is heavily affected by the pesticides in toxication through leaching from the nearly agricultural fields and irrigation canals . The fish affected by the pesticides could pose a health problems to the consumers. According to the Central Insecticide Board, there are about 200 campanies authorized to manufacture formulations of these compounds Chlorpyrifos, Cypermethrin and Endosulfan pesticides preferred due to its quick knock down effect on insects and effective in controlling termites and other household pests. Toxicity experiments for Chlorpyrifos, Cypermethrin and Endosulfan were conducted using statistic system.