A clinicopathologic study was per formed on 14 cases of malignant nondysgerminomatous ovari an germ cell tumors(NDOGCT) treated at the department of obstetrics and gynecology in Korea Cancer Center Hospital between Jan. l987 and,Jun. 1992. The results obtained were as follows ; 1. Median age of the patients was 27.5 years (range, 5 to 54) 2.Clinical symptoms presented were abdminal pain(64.3%), abdominal palpable mass(42.9%), abdominal distension(28.5%) in order of frequency. 3. Histopathologically, 7 cases(50%) were irnmature teratoma, 4 cases(28.6%) were endoder mal sinus tumor, 1 case(7.1%) was embryonal cell carcinoma, 2 cases(14.3%) were mixed germ cell tumor. 4. Bystage, 6 casse(42.9%) were in stage I, 1 case(7.1%) in stage Il, 2 cases(14.3%) in stage III, 3 cases(21.4%) in stage IV, and 2 cases(14.3%) in recurrence. 5, Serum alphafetoprotein was elevated in all patients withendodermal sinus tumor or embryonal carcinoma, and serum CA125 was elevated in about one half of the patients with nondysgerminomatous gerrn cell tumr. 6. l0 cases were managed by salpingo-oophorectomy with poatoperative chemotherapy, 3 cases by hysterectamy and salpingo-oophorectomy with postoperative chemotherapy. 7. Durations of follow up ranged 5 to 66 months, in that period, 5 cases were died, 4 cases were alive with disease and 4 casee wero no evidence of disease. 1 case was loat follow up after operation. All 5 patients were alive who had been treated with REP regirnen. In conelusion, prognosis of malignant NDOGCT is still poor in spite of adjuvant chemotherapy following surgery, and study ineluding appropriate chemotherapeutic regimen may be needed.