A case of gonadoblastoma with dysgerminoma in the left ovary and gonadoblastoma with dysgerminoma and yolk sac tumor in the right of a 10-year-old girl is reported. Her karyotype was 46XX, normal female type. A case of a gonadoblastoma without a Y chromosome is very rare. Furthermore, the prognosis for gonadoblastoma accompanied by germ cell tumors other than dysgerminoma was very poor in the past, but the patient remains well 25 months after the first operation.