The clinical picture of hemorrhagic type Moyamoya disease was analyzed in 20 cases. Hematoma at the basal ganglia was noted in 40% of cases, intraventricular hemorrhage (IVH) in 30%, thalamic hemorrhage with ventricular rupture in 15% and subcortical hemorrhage in 5%. The location was undetermined in two cases (10%) due to bleeding in the pre-computed tomography (CT) era. The frequencies shown above were correlated well to previous reports. In magnetic resonance imaging (MRI) performed 1 year or more after IVH, the primary bleeding site was demonstrated at the lateral wall of lateral ventricle, in portion density weighted and T2 weighted images. MRI can detect the site of old bleeding points and its chronological change if the study is repeated. In a follow-up period of 6.2 years, 35% of the cases had rebleeding once or twice. The second bleeding occurred seven times and the third twice. IVH occurred five times and the most common, basal ganglia hematoma three times while thalamic hemorrhage once. As a result, the rate of good outcome was 60% after the first bleeding and 40% after rebleeding. The mortality rate was 5% after the first 25% after rebleedings. Factors related to rebleedings and their poorer outcome are sex (with women being more susceptible), massive ICH and early recurrence. Rebleeding worsened the outcome. Therefore, prevention of rebleeding is important. From a therapeutic viewpoint, although a close relation between rebleeding and untreated hypertension could not be established, blood pressure control is critical at the both acute and chronic stages. Bypass surgery for bleeding type of Moyamoya disease seems to be less promising than ischemic type, even though a definite answer may not be obtained from our small number of cases.