〔Abstract〕 Objective To investigate the diagnostic efficacy of the nomogram model based on Chinese thyroid imaging reporting and data system(C-TIRADS) combined with shear wave elastography(SWE) and clinically independent risk factors for category IV thyroid nodules. Methods 2D-ultrasound images and SWE images of 256 patients(269 nodules) with category IV thyroid nodules were analyzed. The sensitivity, specificity, and accuracy of the diagnosis by C-TIRADS and SWE were calculated using pathological findings as the gold standard. Receiver operating characteristic(ROC) curves were plotted, and the area under the curve(AUC) was obtained. Independent risk factors for thyroid nodules were screened by univariate and multifactorial logistic regression analyses, a risk model was developed and a nomogram model was plotted, and a calibration curve analysis was used to assess the accuracy of prediction. ROC of the nomogram model was plotted, and the diagnostic efficacy of C-TIRADS, SWE and nomogram model based on independent risk factors was compared according to the AUC in category IV thyroid nodules. Results The sensitivity, specificity, and accuracy of C-TIRADS for differentiating malignant and benign nodules was 0.921, 0.724 and 0.844 respectively, the AUC was equal to 0.822 with a 95% confidence interval(95%CI) of 0.775-0.870. The sensitivity, specificity and accuracy of SWE were 0.701, 0.981, 0.814 respectively, and the AUC was 0.833(95%CI: 0.795-0.872). Multifactorial logistic regression analysis suggested that C-TIRADS classification, mean value of elasticity(E-mean) age and aspect ratio were independent risk factors for identifying benign and malignant thyroid nodules. The sensitivity, specificity and accuracy of the nomogram model established based on the above four factors were 0.957, 0.943 and 0.959, the AUC was 0.963(95%CI: 0.943-0.984), which showed a diagnostic efficacy superior to that of C-TIRADS or SWE alone. Conclusion The nomogram model, constructed based on C-TIRADS, SWE and clinically independent risk factors, can improve the efficacy in diagnosing category IV thyroid nodules, with a better clinical application value.