Abstract: Objective: To study the value of 64-slice Spiral CT angiography in the diagnosis of Moyamoya disease.Material and methods: SCTA findings of 12 cases with Moyamoya disease were analyzed.In 12 cases,Male 5 and Female 7 were studied,age ranged from 16-72years.12 patients with Moyamoya disease were examined both with routine CT scanning and CTA,all performed Volume Rendering(VR),Maximum Intensity projection(MIP),Multi-planar(MPR).Results: Moyamoya vessels which were located in basal ganglia region.Cerebral hemorrhage was found in 9 cases.CTA showed the stenosis or occlusion of arteria and abnormal vessel network.VR was better on showing the stenosis of the vessels and its spatial relation with surrounding structure,MIP and MPR were better on showing abnormal vessel network in brain basal part and branch vessels.Stenosis or occlusion of the Distal portion of the ICA,Proximal portion of the ACA or MCA,and moyamoya vessels of basal ganglia region were demonstrated by DSA(n=6).Conclusion: 64-slice Spiral CT is of great value in the diagnosis of Moyamoya disease.