We are reporting a case of endosulfan poisoning, admitted in a state of altered consciousness, vomiting, and seizure. The diagnosis was based on history, physical examination and positive reports from toxicological screening. After 8 hrs of admission, a sudden rise in EtCO(2), respiratory rate, heart rate, blood pressure, and body temperature was noted. Masseter spasm was there and patient's elbow/knees could not be bent upon manipulation. Caffeine halothane contraction test later confirmed it to be malignant hyperthermia (MH). We suggest that if there is a sudden rise in body temperature, stiffness in limbs or massater spasm in a case of endosulfan poisoning, the diagnosis of MH should be considered as one possibility when etiology is not certain.