For the evaluation of carotid artery stenosis, the conventional measure is to gauge the narrowing or constriction of the inner surface of the carotid artery in the radiological images, and then the severity of stenosis is as a significant indicator for decision-making for intervention. However, much clinical experiences and clinical evidences have demonstrated that plaque stability and vulne-rability are better indicators in evaluation of symptoms, prognosis and revascularization of carotid artery stenosis. In this article, we integrated the advanced progress of carotid imaging techniques such as ultrasonography, computed tomography, magnetic resonance imaging and PET/CT, and analyzed the advantages and disadvantages of these techniques in the evaluation of plaque morphology and stability for clinical references.