Thyroid nodules are one of the signs of many thyroid disorders. Common disorders include nodular goiter, thyroid adenoma, thyroid cyst, subacute thyroiditis, chronic lymphocytic thyroiditis and thyroid cancer. The principles of management of nodules of different nature differ. Inflammatory nodules and simple nodular goiter most often do not require surgical treatment, while thyroid tumors should be treated surgically. Therefore, it is very important to determine the nature of the nodule. When a thyroid nodule is found, a complete history of the patient should be collected and a detailed examination of the thyroid gland and adjacent cervical lymph nodes should be performed. Some relevant medical history, such as history of head and neck or whole body radiation exposure for bone marrow transplantation, family history of thyroid cancer in first-degree relatives, rapid growth of the nodule causing compression of adjacent organs such as trachea, dysphagia, hoarseness, etc., may suggest that the nodule may be malignant. In children, 50% of thyroid nodules are malignant, and young men with a single nodule should also be alerted to the possibility of malignancy. Vocal cord paralysis, enlarged lymph nodes in the neck ipsilateral to the nodule and relative fixation with the surrounding tissue also suggest that the nodule may be malignant. Next, the necessary ancillary tests should be performed, as history and physical examination provide limited information to determine the malignancy of the nodule, while other non-palpable thyroid nodules require ultrasound or other imaging analysis that can show the anatomy. Ultrasound provides important information about the size, shape, texture, borders, calcification, and blood flow signals of nodules, and is noninvasive, quick, and inexpensive. Ultrasound findings of microcalcifications, hypoechogenicity and an abundant blood supply between nodules are further examined to rule out malignancy. CT and MRI are not superior to ultrasound for the diagnosis of benign and malignant thyroid nodules. They provide more precise localization information and surrounding organ contiguity, and in patients requiring surgery, provide more detailed preoperative Radiographic nuclide thyroid scanning can determine whether the nodule is functional, isofunctional (“warm”), or nonfunctional. Malignant tumors generally do not absorb iodine, so the likelihood of a hypofunctional nodule being malignant is generally higher than that of a functional nodule. Low-functioning nodules are 20% likely to be malignant and therefore usually require surgery. Functional nodules are rarely malignant, so cytologic evaluation of these nodules is not necessary. Serum thyroglobulin levels are elevated in most cases of thyroid disease and are neither sensitive nor specific for thyroid cancer. Serum calcitonin is a meaningful indicator, and routine testing of serum calcitonin may improve the overall survival of patients with parathyroid hyperplasia and medullary thyroid cancer by providing early detection. Serum calcitonin >100 pg/ml in unstimulated cases suggests the possibility of medullary thyroid cancer. FNA is the most effective method for evaluating thyroid nodules. Traditionally, FNA biopsies have been classified into 4 categories: undiagnosed, malignant, indeterminate (or suspicious for neoplasia), and benign. FNA is generally more than 90% accurate in the diagnosis of papillary, medullary and undifferentiated carcinomas, as the diagnosis of follicular carcinoma is dependent on the degree of histological invasion and therefore not easily diagnosed with FNA. In multiple thyroid nodules, thyroid cancer may be missed if only the “dominant” nodule or the largest nodule is biopsied by needle aspiration. A satisfactory FNA result requires an adequate amount of tissue and an experienced cytologist, and lesions larger than 4 cm may have sampling errors, while lesions smaller than 1 cm are not easily aspirated. Benign nodules become smaller in diameter, whereas malignant nodules increase in size, albeit slowly. Nodule growth itself is not an indication for malignancy, but it is an indication for repeat biopsy. Some cystic nodules that are never diagnosed on the basis of cytologic findings during repeated biopsies are likely to be diagnosed as malignant at the time of surgery. Combining the history, physical examination and ancillary findings, the possibility of malignant thyroid nodules is basically excluded. Follow-up observation or thyroxine suppression therapy may be performed, and ultrasound may be repeated in 3-6 months for changes in the mass. If the lump becomes smaller, you can continue to take it for six months and then slowly reduce the dosage. However, this method is usually less effective for tumors larger than 2 cm, and it is easy to recur after stopping the medication. For those who are ineffective in taking medication and the lump is persistently growing, surgery is recommended. Given the relatively low malignancy of papillary thyroid cancer, a 3-month observation period will not affect the long-term outcome. It is important to emphasize that thyroid nodules may become malignant during the observation period with or without medication, and therefore should not be taken lightly. It is not advisable to be overly nervous or “indifferent”.