The Brenner tumors of the ovary are uncommon and constitute 1.5-2.5% of all ovarian neoplasms. And their malignant counterparts are rare. Although the first malignant Brenner tumor was described by Von Numers in 1945, only a few malignant Brenner tumors have been reported. The definition and its biologic behavior, and the optimal treatment has not been established. We present a patient who had total abdominal hysterectomy with unilateral salpingooophorectomy due to adenomyosis. The resected ovary had only follicular cysts and the remained ovary was grossly normal . Malignant Brenner tumor developed at the remained ovary 15 years after operation. Operation and adjuvant chemotherapy was applied and patient is alive without evidence of disease. We have experienced a case of malignant Brenner tumor developed at the remained ovary after contralateral oophorectomy with a brief review of literature.