Primary lymphomas of the skull are extremely rare, as fewer than 20 cases have been reported in the literature. We describe the case of a 51-year-old woman with Huntington chorea who presented with forehead swelling. Imaging studies detected an enhancing mass in the skull with some destruction of the underlying bone. These features were suggestive of osteomyelitis. Surgical excision was performed, and the mass was found to be a primary diffuse large B-cell lymphoma. The patient was administered postoperative chemotherapy, and she was in complete remission at the 1-year follow-up.