The first case of typical Foster-Kennedy syndrome, including decreased olfaction of the side of the optic atrophy due to a primary solitary intracranial extraskeletal plasmacytoma, is reported. Its appearance on a computed tomography scan was compatible with a meningioma or subdural hematoma. The patient demonstrated a chronic, corticosteroid-sensitive, relapsing optic neuropathy associated with an elevated sedimentation rate and a monoclonal gammopathy. The diagnosis, treatment, and prognosis of such tumors are reviewed.