Introduction: To determine an effective and non-invasive medical method for evaluating the severity level of extracranial internal carotid artery (ICA) stenosis by comparing the detection performances of contrast-enhanced ultrasound(CEUS) and digital subtraction angiography(DSA). Materials and methods: Thirty-two consecutive patients (7 women and 25 men; mean age: 65.0 +/- 9.4 years, range: 43-78 years) with internal carotid artery (ICA) stenosis were examined by CEUS and DSA. The studies were performed using a Hitachi Preirus ultrasound machine for CEUS and Allura Xper FD20 system (Philips Medical Systems, Nederland B.V.) for DSA. The contrast-enhancing agent used was 1.2 ml SonoVize (Bracco, Switzerland),In addition, the performances of CEUS and DSA in assessing the patency of ICA and suitability of CEA (carotid endarterectomy) were explored. Results: There was no significant difference between the distributions detected by CEUS and DSA for the four groups. The diameter stenosis percentage measured by CEUS strongly correlated with the DSA image measurements. CEUS reliably identified patients with good sensitivity and specificity at the three cut-off values of 100%, 70%, and 50%. CEUS performed better than DSA in assessing the patency of ICA and suitability of CEA. Conclusion: CEUS is an accurate non-invasive imaging test for carotid artery stenosis that is feasible tolerated in patients with different degrees of carotid stenosis.