A fifty-one year old postmenopausal women with a palpable mass in the lower abdomen was admitted. At laparotomy, a left ovarian solid mass measuring 12x10 cm was discovered. Two nodules, about 1 cm in diameter were seen between the layers of broad ligaments. Although the frozen section was reported as benign cystic teratoma, final diagnosis was reported as squamous cell carcinoma arising in benign cystic teratoma with metastasis in the nodules. She was accepted as Stage lib and treated with 6 courses of high dose of cisplatinum and cyclophosphamide. Tumor was found at second-look laparotomy and a second-line chemotherapy was initiated.