Organophosphorus compound poisoning is a common clinical situation encountered in emergency dept. The estimation of pseudocholinesterase levels in plasma help to identify the objective of the study. 50 cases of suspected organophosphorus compound poisoning were randomly selected above 18 years of age, excluding the patients who have taken other drugs with organophosphorus compound and patients with prior hepatic dysfunction. Detailed history and clinical examination were done. The serum levels of enzyme pseudocholinesterase was estimated on first, second, third and sixth day. 60% were males, 40% were females. Age range 18-55 years. Most of the patients were admitted within 4 hours. 50% cases were mild, 26% were moderate and 24% were severe cases. Commonest clinical features were vomiting, diarrhea and abdominal cramps. Common signs were miosis 46%, difficulty in breathing 42%. Patients who survived had raising values of enzyme levels and in patients who expired did not show much increase in enzyme values. Inearly stages of poisoning determining pseudocholinesterase activity forms a reliable test. In patients who survived had values above 4300 U/L and showed increasing levels on successive days indicating better prognosis. Low values of enzymes in early stages of poisoning indicate increased mortality.