【Abstract】 Objective: To explore the application value of computer-aided diagnosis system (CAD) combined with ultrasound elastography in differentiating benign and malignant thyroid nodules. Methods: a total of 148 patients (182 nodules) with thyroid nodules confirmed by surgery or biopsy from June 2019 to December 2020 were selected. All the patients were judged by senior ultrasound doctors before operation, graded by elastography, and classified by CAD system based on acr-tirads and k-tirads guidelines The diagnostic efficiency of the system was evaluated. Results: the diagnostic efficiency of computer-aided diagnosis system, elastography and ultrasound doctor was the highest, with the highest sensitivity, specificity, accuracy and AUC. Compared with elastography combined with CAD and single examination method, the differences were statistically significant (P < 0.05). There was no significant difference between the two groups. Conclusion: the combined application of computer-aided diagnosis system, elastic imaging technology and ultrasonic doctor's interpretation in the differential diagnosis of benign and malignant thyroid nodules is comparable to that of senior ultrasonic doctors, and the diagnostic efficiency is higher than that of the combination of the two methods, and higher than that of single examination method.