3D arterial spin labeling (3D ASL) and CT perfusion (CTP) can evaluate the changes of cerebral blood flow(CBF) after carotid endarterectomy(CEA). The aim of this study is to evaluate the changes of CBF after CEA using 3D ASL and CTP respectively, and to compare the consistency of the two methods. Compared with CTP, changes of CBF values obtained by ASL were similar. ASL has similar evaluation results with CTP. As ASL is a noninvasive imaging tool, it has potential to quantitative evaluate hemodynamic changes after CEA.