SPECT of regional cerebral blood flow was performed using $^{99m}Tc-HMPAO$ in 28 patients with cerebrovascular disease and quantitative analysis was done. Cerebral asymmetry index and percent index of asymmetry of cerebellar hemisphere of patients with cerebral infarction or ischemia were $0.764{pm}0.576$ and $-5.6{pm}7.1%$ and those of intracranial hemorrhage was $0.416{pm}0.251$ and $-2.5{pm}4.1%$ respectively. According to PIA of cerebellar hemisphere, 12 patients showed crossed cerebellar diaschisis. $^{99m}Tc-HMPAO$ SPECT seemed to be a useful tool for the evaluation of regional cerebral blood flow.