Primary angiitis of the central nervous system is a rare and difficult entity.Here we represented the clinical and pathological features of a patient with little response to steroid before definite diagnosis.The 50-year-old male had a fluctuating disease course for more than 3 years.He presented visual disorders,seizure,cognitive impairment,hypersomnia,unsteady gait,dysphasia,dysphagia,and incontinence.Magnetic resonance imaging showed multiple,supratentorial and infratentorial abnormal signals,while cerebrospinal fluid and cerebral angiography were normal.Magnetic resonance spectrum showed a decrease of N-acetyl-aspartate.Brain biopsy revealed nongranulomatous lymphatic vasculitis with reactive gliosis,cicatrization,demyelination and focal hemorrhages.