The use of pesticides and fertilizers has increased rapidly in Pakistan. Pesticide use in Pakistan increased seven-fold in quantity between 1981 and 1992, from 915 million tons to 6,865 million tons of which 80% were organophosphate. Several studies have reported the toxicological issues and adverse effects of pesticides in aquatic biodiversity. The present study included the effects of cypermethrin on cholinesterase activity and protein content against Rana tigrina. After preliminary experiments of the under test compound, two different doses were selected for the studies. It was observed that at the dose of 1% and 0.1% cypermethrin treated frogs, a total reduction in protein contents was found to be 79, 69% in kidney and 76, 44% in liver respectively, as compared to the control. The cholinesterase was found to be inhibited by 36, 35% in kidney and 52 and 47%in liver respectively, when frog were treated with cypermethrin at aforesaid doses. Based on results it is concluded that cypermethrin has reduced protein contents and cholinesterase activity in Rana tigrina. The research techniques and information are helpful for graduate and research students of Biological Sciences.