Patients with grade 4 thyroid nodules are advised to eat a diet of light foods with balanced nutrition. If hyperthyroidism is present, the intake of iodine-rich foods, such as kelp and marine fish, should be reduced. Pay attention to regular rechecks, or make judgment based on the results of thyroid puncture. Thyroid nodules are clinically categorized into 6 grades according to the ultrasound results, and the higher the grade, the higher the possibility of malignant changes. Thyroid nodules grade 4 are clinically categorized into three grades: grade 4a has a malignant possibility of 2%~10%, grade 4b has a malignant possibility of 10~50%, and grade 4C has a malignant possibility of 50%~90%. When grade 4 nodules are found clinically, first attention should be paid to evaluating the possibility of malignant transformation of thyroid nodules, and if necessary, it is necessary to evaluate and determine the necessity of surgery based on the test results of fine needle aspiration of thyroid nodules. For patients who cannot undergo fine-needle aspiration, ultrasonography is recommended, and surgery may be considered if the thyroid nodule is found to be rapidly increasing in size over a short period of time. For patients with grade 4 thyroid nodules, please consult the Department of Thyroid and Breast Surgery or the Department of Endocrinology of a regular hospital, and choose the appropriate treatment under the guidance of the doctor, so as to avoid delaying the condition.