Ultrasound is valuable in assessing the benignity and malignancy of thyroid nodules, although it is not a pathological diagnosis and cannot be done necessarily as benign or malignant. No expert would dare to say that a nodule is benign or malignant, but it is still an imaging diagnosis. The diagnosis of benign and malignant is based on some features, such as whether the nodule is flat or round, vertical or horizontal growth, clear or blurred border, and whether the structure inside is cystic, mixed cystic or solid, or whether the echogenicity inside is hypoechoic, isoechoic or hyperechoic, and whether there is calcification inside, and if there is calcification, whether it is coarse calcification, fine calcification, microcalcification, or peripheral circumferential calcification If there is calcification, is it coarse, fine, microcalcification, or peripheral circumferential calcification? Based on the above indications, a composite score is performed, and based on the overall score, a classification is then made. The risk of malignancy varies with different classifications, and the higher the classification, the higher the risk of malignancy. If it is category I, it is usually a benign lesion, category II has a 2% risk of malignancy, category III has a 5% risk of malignancy, category IV has an increased risk of malignancy of 5%-20%, and category V has a risk of malignancy of 20% or more. So nowadays it is more about scoring and classifying different thyroid ultrasound features that suggest malignant risk. Overall, it will give an assessment of whether the risk is biased towards benign or malignant, but specific benign and malignant, or pathological examination should be done, subject to pathology, imaging is still imaging after all, and can only provide an assessment of malignant risk.