【Abstract】 Objective To investigate the effects of transcranial Doppler monitoring of cerebral vascular reactivity in Department of neurology.Methods 78 hospitalized patients with carotid artery stenosis were selected as the observation group, and the other 78 without carotid artery stenosis patients at the same period were selected as the control group. All patients were examined by transcranial Doppler ultrasound and were given the continuous monitoring of cerebral artery of cerebral blood flow velocity changes, the vasomotor reactivity (VMR), cerebrovascular reserve movements (CRC) calculation, respiratory depression index (BHI) and other indicators were recorded and given correlation analysis.Results There were no significant differences in the gender, age, body mass index, blood glucose, systolic blood pressure, diastolic blood pressure, total cholesterol and triglyceride between the two groups (P＞0.05). The ultrasound Vm, Vs and Vd values in the observation group were significantly lower than that in the control group, while the PI and RI values in the observation group were significantly higher than that in the control group. The difference were all statistically significant (P＜0.05). The values of CRC, BHI and VMR in the observation group were 9.35±1.62, 0.42± 0.21 and 0.18±0.14, respectively, which were significantly lower than that of the control group (12.49±3.10, 0.79±0.14 and 0.35±0.11) (P＜0.05). Linear correlation analysis showed that CRC, BHI, VMR were significant positively correlated to the Vd, Vs and Vm in the observation group(P＜0.05), while were showed significant negative correlated to the RI and PI (P＜0.05).Conclusion Transcranial Doppler monitoring of cerebral vascular reactivity is dynamic, which can provide the basis for finding brain perfusion abnormalities in patients, and the cerebral vascular reactivity has certain correlation to the ultrasonic. It is conducive to guide for judging the severity of illness and prognosis evaluation.