A solid well-circumscribed ovarian tumor in a 63-year-old Japanese woman is reported. Histologically, the tumor consisted predominantly of a hemangiomatous component with a small cyst lined by a respiratory ciliated epithelium. The remaining ovarian stroma showed a marked proliferation of luteinized cells that were strongly positive for inhibin immunohistochemically. Neither dermoid nor other teratomatous components were found, even in the serial sections of the tumor. To date, vascular tumors of the ovary are uncommon and some cases of ovarian hemangioma have been reported. However, their origin, whether a monodermal teratoma or a true neoplasm arising in the ovarian stroma, has not yet been elucidated. When a hemangiomatous proliferation is found in an ovarian tumor, a thorough microscopic search for teratomatous components is necessary before diagnosing the tumor as a pure hemangioma.