Objective To study the effect of tortuous internal carotid artery on cerebral hemodynamics. Methods Digital subtraction angiography was performed in cerebral ischemic stroke patients in order to screen out those with tortuous internal carotid artery but without stenosis or blocking of the artery. Then, the information of the patients screened out was analyzed and the developing time of the middle cerebral artery was observed. Finally, haemodynamics of the middle cerebral artery with transcranial color Doppler was evaluated. Results Compared with patients without tortuous internal carotid artery, those with tortuous internal carotid artery were older and more likely to be patients of hypertension. In addition, the developing time of their middle cerebral artery was obviously extended ［patients with the tortuous artery (2.08±0.34) s in contrast to patients without the tortuous artery (1.84±0.24) s］. Their systolic blood flow velocity was（75.77±15.09）cm/s and the mean velocity of blood flow was（49.60±10.37）cm/s, slower than those in the control group ［（107.52±24.17）cm/s and (65.38±16.22）cm/s］, and the vascular pulsation index and resistance index were both lower than those in the control group. Conclusions Tortuous internal carotid artery is closely related to age and hypertension, causing changes in cerebral hemodynamics. Cerebral hemodynamic changes in patients with tortuous internal carotid artery may be one of the causes of stroke.