Autonomic hyperreflexia is a syndrome of massive reflex sympathetic discharge that occurs in patients with chronic spinal cord lesions above the major sympathetic splanchnic outflow (T 4 -T6). We experienced autonomic hyperreflexia that occured in a patient with spinal cord trans-section at T5 level during general anesthesia with O2-N2O-halothane. Hypertension was controlled with intravenous infusion of sodium nitroprusside (1-2 ug/kg/min) and ventricular arrhythmia was treated with intra- venous lidocaine. We recommend that direct acting vasodilators are useful drugs to control hypertension in autonomic hyperreflexia during anesthesia in patients with chronic spinal cord injury.