Objective: To assess the value of thyroid imaging reporting and data system (TI-RADS) for qualitative diagnosis of thyroid nodules. Methods: The conventional ultrasound image data from 235 patients with total of 432 thyroid nodules (299 benign nodules and 133 malignant nodules) that were confirmed by surgical and pathological findings were retrospectively analyzed. The ultrasound characteristics that had statistical significance in differentiation between benign and malignant lesions were screened, and the nodules, according to the ultrasound characteristics, were divided into 1-5 grades using TI-RADS classification standard, and then the grading results were compared with the final pathological results. Results: Statistical analyses showed that lesions with ill-defined border, irregular shape, solid echo, microcalcifications, irregular vascular pattern, and a short-to-long axis ratio ≥1 or the presence of abnormal lymph nodes were malignant ultrasound characteristics for nodules (all P<0.05). Using grade 3 as the criterion for classifying benign and malignant lesion, the sensitivity, specificity, and accuracy of TI-RADS classification was 83.5%, 91.0% and 88.7%, respectively; if only grade 1-2 (representing benign lesion) and grade 4-5 (representing malignant lesion) were considered, with exclusion of the dubious grade 3, the sensitivity, specificity, and accuracy of TI-RADS classification was 90.1%, 98.9% and 96.2%, respectively. Conclusion: TI-RADS has high sensitivity, specificity, and accuracy; its application is helpful for interpretation of the ultrasonic evaluation and, thereby for making a proper treatment plan. So it has great practical value.