Objective：Using transcranial Doppler ultrasound(TCD) to evaluate the cerebral hemodynamic changes of Alzheimer’s disease(AD),probe into the relationship between cognition impairment and this changes and diagnosis value of TCD.Methods：AD and non-demented controls were recruited.TCD was employed to assess mean flow velocity (MFV) and pulsatility index(PI) of intracranial arterial segments.Results: MFV in AD group was lower than NDC (P<0.05), while PI in AD group was higher (P<0.05), MFV was positively related to MMSE while PI was negatively correlated toSMMSE in AD group.ROC curves showed that the vast majority of the measurements for PI and MFV in the arteries of interest were significantly different from an ROC area of 0.7. Conclusion:Our study shows that decreased MFV and increased PI was linked to this dementia, TCD and might have a diagnostic potential and TCD may also become instrumental in the efficacy evaluation of drugs and other treatment modalities.