An 18-year-old woman presented with a malignant fibrous histiocytoma (MFH) originating in the orbit and invading the frontal and temporal base of the skull manifesting as exophthalmos and double vision that had persisted for 2 months. Magnetic resonance imaging revealed a tumor in the left orbit that extended as far as the frontal and temporal base of the skull. The tumor was treated by radical resection with conservation of the eyeball and its contents, followed by orbit wall reconstruction. The histological diagnosis was MFH. Local radiotherapy was administered postoperatively. The preoperative symptoms improved, and there has been no evidence of local recurrence or metastasis in the year since the surgery. In this case, radical resection of the tumor was essential. Furthermore, the adjuvant therapy was apparently successful, probably because this histological type of tumor is highly sensitive to radiotherapy.