A 55-year-old female presented with a rare solitary plasmacytoma restricted to the skull vault without systemic myelomatosis. She had a 9-month history of a slowly growing soft mass in the right temporal region. Neuroradiological examination revealed a skull defect and an extradural tumor. The whole layer of the skull was destroyed by the tumor, but the dura was not involved. The tumor was totally removed, and postoperative radiotherapy was given. Follow-up examination after 2 years showed she was free from local recurrence or evidence of systemic involvement. Complete surgical resection with adjuvant radiation therapy is the treatment of choice. Although the prognosis is good, regular lifelong examinations for myelomatosis are required.