Polycythemia vera is a hematologic malignancy characterized by excessive proliferation of erythroid, myeloid and megakaryocytic elements within bone marrow, resulting in increased red cell mass, frequently leukocytosis and thrombocytosis. Patients with absolute erythrocytosis can be categorized into primary; those in whom excessive production of red cells results from a disorder intrinsic to the erythroid progenitor cells of bone marrow, or secondary; from excessive stimulation of an otherwise normal marrow by substance such as erythropoietin. Polycythemia vera is a disease process in which control prior to surgery decreases the frequency of perioperative complications. Surgery was postponed on an 61-year-old female patient found to have a hematocrit of 59%. She was phlebotomized and treated with hydroxyurea. Her hematocrit was decreased to 43%. General anesthesia was maintained with N2O-O2-enflurane after tracheal intubation. No thrombotic or bleeding problem was developed and she was discharged without complication at 14th day after operation.