Objective To compare the results of transcranial Doppler (TCD) in patients with type Ⅱ diabetes and patients with no diabetes to explore the clinical value of TCD in patients with diabetes. Methods The results of TCD were recorded in 60 cases of type Ⅱ diabetes and 60 cases of no diabetes, and then, statistical analysis was performed. Results The patients with type Ⅱ diabetes showed significantly increased peak-systolic velocity, mean velocity and pulsatility indexes of the intracranial blood vessels as compared with the patients with no diabetes (P＜0.05). Conclusion TCD can help to make objective evaluation in patients with cerebrovascular disease and type Ⅱ diabetes,showing its significance in preventing the cerebrovascular disease in patients with diabetes.