The five criteria for the benignity and malignancy of thyroid nodules are used to judge the benignity and malignancy of thyroid disease and are divided into five levels. Grade 1 is when the patient has a normal thyroid gland without thyroid disease; Grade 2 is when the patient has a thyroid nodule but it does not affect the patient’s normal life much; Grade 3 is when the patient has a thyroid nodule and it is enlarged; Grade 4 is when the patient’s thyroid nodule may have malignant lesions; and Grade 5 is when the patient’s thyroid nodule can be diagnosed as malignant. This five-level classification is widely used in clinical practice to diagnose thyroid nodules, to help assess the patient’s condition, and to help physicians develop relevant treatment plans. Patients with grade V thyroid nodules usually require chemotherapy and should be treated with strict dietary control, good mood, and prevention of tumor metastasis or blood spreading.