Abstract: Objective To study the role of contrast-enhanced ultrasonography in differential diagnosis of enlarged neck benign and malignant lymph nodes. Methods Sixty patients with 92 enlarged neck lymph nodes admitted to our hospital received routine ultrasonography and contrast-enhanced ultrasonography to observe the distribution of their lymph nodes. The time-intensity curves for benign and malignant lymph nodes were analyzed and compared with those of pathologically- diagnosed benign and malignant lymph nodes. The diagnosis accuracy was compared before and after contrast-enhanced ultrasonography. Results Contrast-enhanced ultrasonography showed intense homogeneous enhancement in 34 out of the 42 benign lymph nodes and non- homogeneous enhancement in 38 out of the 50 malignant lymph nodes. The time-intensity curve for benign lymph nodes displayed a fast-down pattern while the malignant lymph nodes showed a slow-down pattern. Lymph node puncture and postoperative pathology revealed that, of the 92 lymph nodes, 42 were benign (45.7%) and 50 were malignant(54.3%). The sensitivity, specificity, and accuracy of routine ultrasonography and contrastenhanced ultrasonography were 76%, 80%, and 78% respectively, and 92%, 95% and 93% respectively. Conclusion Contrast-enhanced ultrasonography can provide valuable evidence for the differential diagnosis of enlarged neck benign and malignant lymph nodes.