The results of 225 operations made in 140 patients with Moya-Moya disease are analyzed. All the patients had clinical manifestations of this disease and were examined in accordance with the approved protocol of the Unit of Neurosurgery, Nagoya Daini Red Cross Hospital (Nagoya, Japan). The examination included computed tomography, magnetic resonance imaging, magnetic resonance angiography, preoperative angiography, single photon emission computed tomography with acetazolamide challenge. The surgical method consisted of a combination of direct arterial microanastomosis and indirect synangiosis (EMS, EDAS, EGS, cranial burr hole). The number of surgical complications was minimal (2.9%). There were excellent and good clinical results (disappearance of clinical symptoms or clinical improvement) in 92.9% of cases. Postoperative examinations confirmed the high percentage of positive results as cerebral circulation normalization in 97.1% of cases. The results of surgical treatment provided strong evidence that progression of the disease could be prevented.