AIM: To evaluate the diagnostic value of thyroid fine needle aspiration cytology (FNAC) and BRAF and RAS gene mutation screening for thyroid cancer. METHODS: From January 2022 to December 2022, a total of 597 patients underwent FNAC in our hospital, of which 25 patients were removed due to specimen dissatisfaction, 282 patients had BRAF/RAS genetic testing, and 227 patients underwent surgery. Using postoperative pathological results as the gold standard to analyze the sensitivity, specificity and diagnostic accuracy of FNAC, BRAF/RAS and their combined detection in the diagnosis of thyroid cancer. RESULTS: For patients with FNAC and postoperative thyroid malignancy, the positive rate of BRAF/RAS gene was 42.9%, and the positive rate of BRAF in TI-RADS above 4B was 69.2%, but the difference was not significant (P=0.116).The sensitivity of FNAC alone for thyroid cancer was 82.8% and specificity was 100.0%. Combined with BRAF gene detection, the sensitivity was improved to 89.3%, specificity was 96.6%, and the accuracy of diagnosis increased from 82.8% to 85.9%.CONCLUSION: In patients with thyroid nodules, high-risk patients (especially 4B and above) were screened by ultrasound TI-RADS classification, and combined FNAC and BRAF gene testing can improve the diagnostic rate of thyroid cancer.