A case of extramedullary plasmacytoma with its unusual appearance is reported. This is the second reported case in world literature affecting the paranasal sinuses with intracranial extension. The role of surgery is to obtain tissue for diagnosis and to excise residual disease. Radiotherapy is the treatment of choice and long-term follow-up is necessary for monitoring disease recurrence. The overall 10-year survival is about 50%. The case is discussed with a general review of the management of this pathology.