Objective To evaluate the diagnostic efficacy of AmCAD-UT Detection for benign and malignant thyroid nodules.Method The 166 thyroid nodules were graded TI-RADS by physicians according to their conventional two-dimensional ultrasound and two-dimensional ultrasound combined contrast-enhanced ultrasound (CEUS) features, and were graded automatically by AmCAD-UT Detection. The receiveroperator characteristic (ROC) curve was established based on the gold standard of postoperative pathological results, and the area under the curve(AUC)of the three methods was compared. And the applicable cutoff point for differentiating benign and malignant thyroid nodules was found, and the sensitivity, specificity and accuracy of CAD were compared with conventional two-dimensional ultrasound and two-dimensional ultrasound combined CEUS,and analyzed the difference of ultrasonic features described by CAD system in benign and malignant nodules to evaluate the diagnostic efficacy.Result The diagnostic ability of the three methods was compared: two-dimensional combined CEUS > CAD > conventional two-dimensional ultrasound(The AUC of the three methods was 0.930,0.859and 0.833, respectively). The sensitivity and accuracy of CAD were higher than conventional two-dimensional ultrasound,the specificity was lower than conventional two-dimensional ultrasound,and the specificity and accuracy of two-dimensional combined CEUS were higher than those of CAD(P＜0.05). Hypoechogenicity、microcalcifications、irregular margins were available for identifying benign and malignant nodules.Conclusion the AmCAD-UT Detection can detect sensitively thyroid malignant nodules, improve the accuracy of diagnosis, quantify features of thyroid nodules comprehensively and accurately, and have a significant clinical application value.