Objective: To summarize and analyze the physiological mechanism of cerebral autoregulation (CA) and the pathophysiological change after stroke, and explore the different methods on CA measurement as well as the application of CA on neurological study. Data sources: We searched for the correlative articles on CA in the Medline from January 1959 to December 2004 by the computer with the key word of "cerebral autoregulation" in English. At the same time, China Journal Full-text Database was retrieved for the Chinese articles related to CA published from January 1994 to December 2004 using the key word of "cerebral autoregulation". Study selection: All the data were checked firstly. Inclusion criteria: 1 about the definition, physiological mechanism, influencing factors and detections of CA. 2 retrospect research of concrete events. Exclusion criteria: repetitive study. Data extraction: Totally 49 articles were screened out in accordance with the criterias, and 21 of them were excluded due to the repetitive contents. Among 28 inclusive articles, 16 ones were related with the definition and physiology of CA, 5 were related with the CA changes after acute stroke, and 7 were related with case reports. Data synthesis: CA provides an important protective mechanism by ensuring that the cerebral circulation maintains comparatively constant blood flow over a wide range of perfusion pressures. Influenced by multiple factors, CA is impaired and decreased after stroke. Conclusion: Cerebral autoregulation is of great importance in maintaining near-constant blood flow over a wide range of perfusion pressures. Further study on CA may contribute to investigate the pathogenesis of stroke.