Organophosphorous poisoning (OP poisoning) is common poisoning specially in developing countries like India. Laboratory parameter like erythrocyte cholinesterase activity has been used to support clinical diagnosis and to predict prognosis and it is expensive. Pseudo cholinesterase is cheaper alternative but it is less reliable. CPK is a cheaper investigation and is easily performed in all laboratories. Hence this study was done to evaluate role of Creatine phosphokinase levels to support clinical diagnosis as well as predicting prognosis in acute OP compound poisoning. Material and Methods: It was a prospective observational study which included 50 patients who presented within 6 hours of consumption of OP compound after considering inclusion and exclusion criteria. Patients were categorized into mild, moderate and severe poisoning according to POP score and initial CPK levels were noted. Data expressed in percentages and Chi–square test was used to know statistical significance. Results: Out of 50 patients, 28 (56%) had mild, 16 (32%) had moderate and 6(12%) had severe poisoning. Initial CPK levels were positively correlated with POP score. Four deaths occurred in our study, out of which one had moderate poisoning and three patients had severe poisoning. Conclusion: Initial CPK levels correlated with severity of OP compound poisoning and mortality.