Objective:To explore the advantage of thyroid biopsy and evaluate detection in the application of thyroid cancer cervical lymph node dissection operation guidance, and provide evidence-based basis for guiding PTC patients whether to receive lateral dissection.Methods:The data of 258 patients with thyroid papillary carcinoma admitted to Department of Thyroid Surgery, Affiliated Hospital of Chengde Medical College from April 2018 to December 2019 were retrospectively analyzed. All patients were admitted to the hospital for ultrasonic examination of cervical lymph nodes. According to the examination results, thyroid biopsy and puncture eluent were performed for patients with suspicious signs of metastasis. Patients with positive test results and with metastatic signs in initial ultrasonic examination received lymph node dissection in the cervical region. All patients underwent pathological examination postoperatively to diagnose the lymph node metastasis, and to evaluate the sensitivity, specificity and accuracy of the detection of the patients with lateral clearance.The measurement data was expressed as mean±standard deviation ( Mean± SD), and the count data was expressed as n(%). The software of SPSS21.0 was used to conduct statistical analysis. Results:All 258 patients were successfully completed the diagnosis of various diagnostic methods. Combined with the postoperative pathological diagnosis results, the accuracy rate of ultrasonic diagnosis of lymph node metastasis was 74.42%, the accuracy rate of FNAC diagnosis was 82.95%, the accuracy rate of FNAC-Tg diagnosis was 87.98%, and the accuracy rate of FNAC-Tg diagnosis was 94.96%. The diagnostic sensitivity of ultrasound, FNAC, FNAC-Tg and FNAC-Tg was 73.60%, 81.72%, 91.01% and 95.83%, respectively, and the diagnostic specificity was 76.25%, 86.11%, 79.71% and 88.41%, respectively. In every four months for a time span since April 2018, the average length of hospital stay for patients with each span was (9.17±1.30), (8.39±1.21), (7.94±1.03), (7.46±0.94), (7.33±0.82) d, their neck area incidence of lymph node metastasis were 17.6%, 21.3%, 15.7%, 12.9%, 11.8%, side clear surgical patients accounted for 42.3%, 37.5%, 30.9%, 26.6%, 19.4%. The incidence of lymph node metastasis was 86.8%, 79.4%, 84.5%, 93.2% and 98.1%, respectively.Conclusion:FNAC-Tg method is used in the diagnosis of thyroid papillary carcinoma patients with high sensitivity and specificity of lymph node metastasis, which has certain value in guiding patients whether to perform lymph node dissection.