摘要Objective:To observe the therapeutic effect of Yangxue Qingnao granule (养血清脑颗粒,YXQNG) in treating chronic cerebrovascular insufficiency (CCI) and its possible mechanism. Methods:Eighty-three patients with CCI were randomly divided into YXQNG and nimodipine (ND) groups, the score of vertigo and the change in cerebral blood velocity before and after treatment were observed. And in the animal experiment, the authors adopted bilateral ligation of cervical carotid communis artery to establish CCI rat models in order to observe the effect of YXQNG and ND on incubation period of vertigo in rats and on memory performance. Results: After clinical treatment, the vertigo score of YXQNG group was 2.34, and that of the ND group was 4.18, the comparison between the two groups showed that the difference was significant (P＜0.05). After treatment, the middle cerebral artery mean velocity (MCA Vm) of YXQNG group was 64. 78cm/s, vertebral artery mean velocity (VA Vm) was 29.78 cm/s, while that of ND group was 60.34 cm/s and 23. 23 cm/s respectively, the comparison between these two groups showing statistical significance and the difference being obvious (P＜0.05). Experimental study showed that the rats in the model group after 12weeks learning and memory were markedly lowered, the vertigo incubation period significantly lengthened,and compared with that of the model group, learning and memory of the YXQNG group was markedly improved and vertigo incubation period shortened, with the difference from that of the ND group insignificant, P ＞0.05. Conclusion: YXQNG could effectively improve CCI patients' vertigo and other clinical symptoms and increase the cerebral blood flow, lessen the vertigo incubation of model group rats, elevate model group rats'memory performance.