A 43-year-old man without a previous episode of uveitis presented with slowly progressive neurological symptoms that appeared within the past year such as dysarthria, ataxic gait, and behavioral changes. Brain MRI findings showed atrophic lesions in the brainstem and cerebellum. Because these clinical symptoms and abnormal MRI findings indicated spinocerebellar degeneration as the initial diagnosis, he was admitted to our hospital. On admission, we noticed that he had non-neurological manifestations of Behçet disease, such as stomatitis, genital ulcers, and folliculitis. HLA-B51 was positive. He also showed pleocytosis (29 cells/mm