We report MRI changes in a spontaneous intracranial hypotension(SIH). The patient was 29-year-old woman, who developed headaches in upright position, nausea, and vomiting preceded by pressure feeling of ears. Neurological examination was unremarkable except for hyperreflexia in the lower extremities. Lumbar punctures revealed very low opening pressure, a mild elevated CSF protein and a mild pleocytosis. No evidence of underlying systemic or neoplastic diseases was noted. The brain and cervical MRI showed diffuse and continuous pachymeningeal enhancement with gadolinium. Her symptoms gradually improved within two months without any treatment, and follow-up MRI showed resolution of the abnormalities within five months. The dural enhancement with gadolinium seen in the SIH should be kept in mind in case of hypertrophic pachymeningitis of unknown etiology, and be differentiated from such diseases as hypertrophic pachymeningitis associated with infectious, neoplastic diseases or sarcoidosis.