Sturge-Weber syndrome (SWS) is a phakomatosis characterized by vascular nevus flammeus, leptomeningeal venous angiomatosis, seizures, dementia, hemiplegia, hemianopsia, and glaucoma. Various imaging findings (gyriform calcification, atrophy of the ipsilateral hemisphere, leptomeningeal enhancement, ipsilateral choroid plexus enlargement, thickened calvarium, enlargement of paranasal sinuses and mastoid air cells, enlargement of deep veins, and white matter change adjacent to leptomeningeal enhancement) are seen in SWS. We examined the efficacy of CT and MR imaging in making the diagnosis in 14 patients. All patients underwent CT and MRI, and 11 of 14 patients underwent contrast-enhanced MRI. The most specific finding was leptomeningeal enhancement. Gyriform calcification, atrophy of the ipsilateral hemisphere, and ipsilateral chroid plexus enlargement were seen at high frequencies. Thickened calvarium was more frequent in adult patients. Enlargement of paranasal sinuses and mastoid air cells, enlargement of deep veins, and white matter change adjacent to leptomeningeal enhancement were seen in some (3-5) patients. A combination of findings of plain CT and MRI (including postcontrast MRI and MR venography) are useful for diagnosing SWS.