Abstract: Objective: To evaluate the application value of computed tomography perfusion(CTP) imaging in the diagnosis of adult Moyamoya disease(MMD). Methods: Fifteen patients with adult MMD confirmed by DSA were selected. CTP were performed in all patients and 10 healthy volunteers. The CTP parameters including cerebral blood flow(CBF), cerebral blood volume(CBV), and mean transit time(MTT) were measured and compared between the MMD group and normal control group. Results: All patients were found abnormal perfusion regions of the brain. CBF and CBV values were significantly lower, and MTT values were obviously higher in the fronto-temporal lobes in the MMD group than normal controls(P < 0.05). In contrast, no significant decrease of CBV value in basal ganglia region was observed in the MMD patients. Conclusion: CTP is a useful method to obtain functional imaging of cerebral microcirculation, which can be a noninvasive assessment of the abnormalities of cerebral perfusion changes in adult MMD before surgery.