It has been emphasized that continuous monitorings of arterial pressure, central venous pressure, electrocardiogram, blood gas analysis, serum electrolytes, body temperature, hematacrit and urinary output are mandatory for the anesthetic management of pheochromocytoma. In addition, it is necessary for the anesthetists to understand pharmacologic effects of drugs which influence the peripheral vascular tone and cardiac excitability. We experienced recently anesthetic management of two cases of pheochromocytoma; one raised problems of ventricular arrhythmias and hypertension that aggravated nature of arrhythrmias by increasing blood pressure and responded favorably to treatment with propranolol and trimetaphan. Tumor of this case originated from abdominal aortic wall. The other was managed by injection of d-tubocurarine which induced narrowing of pulse pressure by depletion of increasing systolic pressure and accompanied tachycardia without cardiac decompensation. We have reported proper anesthetic managements of two cases of pheochromocytoma with N₂O O₂-halothane anesthesia and reviewed literatures in discussion.