Objective：To investigate the value of contrast-enhanced ultrasound combined with serum IL-17, SIL-2R and TG in the differential diagnosis of lymph node metastasis of papillary thyroid carcinoma and tuberculosis of cervical lymph nodes. Methods：Retrospective analysis of 59 patients (metastatic group) and 63 patients (tuberculosis group) who received neck and thyroid contrast-enhanced ultrasonography in our hospital from January 2015 to October 2020 and were pathologically confirmed to have lymph node metastasis of thyroid papillary carcinoma (metastatic group) and cervical lymph node tuberculosis (tuberculosis group). The lymph node region, ratio of length to short diameter, hilum, internal necrosis, calcification, blood flow, resistance index, and contrast-enhanced pattern were observed. Serum levels of IL-17, SIL-2R and TG were detected in all patients. Ceus lymph node and serum indexes were compared between the two groups. The diagnostic sensitivity and specificity of contrast-enhanced ultrasound and serum IL-17, SIL-2R and TG in differential diagnosis of lymph node metastasis of papillary thyroid carcinoma and tuberculosis of cervical lymph nodes were analyzed. Results：In patients with lymph node metastasis of papillary thyroid carcinoma, microcalcification was more common on routine ultrasound, and crude calcification was more common on cervical lymph node tuberculosis. The difference between the two groups was statistically significant (P = 0.000), while there were no statistically significant differences in long-diameter/short-diameter ratio, hilum, internal necrosis, and blood flow imaging between the two groups (P > 0.05). Patients with lymph node metastasis of papillary thyroid carcinoma were mainly in areas III and IV, accounting for 76.29%; patients with tuberculosis of cervical lymph nodes were mainly in areas II, III and IV, accounting for 74.58%, with no statistically significant difference between the two (P = 0.129). There was no significant difference in enhancement patterns between patients with papillary thyroid carcinoma with lymph node metastasis and patients with cervical lymph node tuberculosis (P > 0.05).Among them, there were 36 cases (36/52,69.23%) with thin ring in lymph node metastasis of inhomogeneous enhanced thyroid papillary carcinoma, and 42 cases (42/54,77.78%) with inhomogeneous enhanced tuberculosis of cervical lymph node and thick ring in lymph node metastasis. The difference between the two groups was statistically significant (P = 0.000). The expression levels of IL-17, SIL-2R and TG in patients with lymph node metastasis of thyroid papillary carcinoma were higher than those in patients with tuberculosis of cervical lymph node, and the differences were statistically significant (P = 0.000). The area under the CEUS curve was 0.781, and the diagnostic sensitivity and specificity for the differential diagnosis of the two lesions were 61% and 82%.The area under serum IL-17, SIL-2R and TG curves was 0.673, and the diagnostic sensitivity and specificity of the two lesions were 55% and 71% respectively.The area of CEUS combined with serum IL-17, SIL 2R and TG curves was 0.915. The diagnostic sensitivity and specificity of CEUS combined with serum IL-17, SIL 2R and TG were 83% and 94% respectively for the differential diagnosis of the two lesions. Conclusion：Contrast-enhanced ultrasound can provide enhanced lymph node characteristic information, the serum IL - 17, SIL - 2R, TG can to a certain extent, providing that the performance of benign and malignant lesion, lymph node metastasis of papillary thyroid carcinoma and cervical lymph node tuberculosis were diagnosed with certain value, and the two combined diagnostic value is superior to the single diagnostic performance, help the differential diagnosis.