Two cases of anesthetic experience for excision of pheochromocytoma were presented, one was diagnosed by abdominal computed tomography and urinary VMA level checked after cardiac arrest during previous anesthetic induction for gastric polypectomy at private clinic. The other case was diagnosed by upper GI series and abdominal sonography. Anesthesia was managed with glycopyrrolate and meperidine for premedication, thiopental for induction, isoflurane-nitrous oxide-oxygen for maintenance, pancuronium and vecuronium for muscle relaxation, and nitroprusside for controlling severe hypertensive episode. We experienced marked fluctuation of blood pressure during anesthetic course. Severe hypotension followed removal of tumor, which was corrected by rapid transfusion and infusion of crystalloids. Postanesthetic recovery and course were uneventful.