The presence of carotid vulnerable plaque plays an important role in the pathogenesis of ischemic stroke, therefore, the identification of vulnerable plaques is of important clinical significance in the diagnosis, treatment and prognosis in patients with stroke. Current imaging methods still present some challenges for the diagnosis of such plaques. With the development of ultrasound imaging and related technologies, ultrasound can not only screen the basic features of carotid artery stenosis and plaque, but also provide early indication on plaque vulnerability. This manuscript will review the application and progress of ultrasonic evaluation of vulnerable plaques from four aspects：plaque composition, fiber cap thickness, neovascularization and plaque morphology.