For the localization of thyroid nodules, the size and cystic solidity are now relatively easy to determine, but the most critical aspect of the diagnosis of thyroid nodules is the characterization, as an important surgical reference value of the characterization, inexperienced doctors are more difficult to judge, which requires experienced thyroid specialists based on years of experience and auxiliary tests to determine. 1. Pay attention to the medical history: malignancy is more likely in men, children or adolescents with solitary nodules, and particular attention should be paid to the possibility of malignancy for those who have received radiation to the head and neck. For Hashimoto’s thyroiditis and cold nodules based on primary hyperthyroidism, malignancy is also more likely. Patients with a family history of thyroid cancer or multiple endocrine tumors should be alerted to the possibility of malignancy if they have a thyroid nodule. 2.Patients with sudden discovery of single thyroid nodule with progressive enlargement or obvious enlarged lymph nodes in the neck within a few weeks or months should be alert to the possibility of thyroid cancer. 3.Ultrasound: Ultrasound is the main means of examination for thyroid nodules. The accuracy of the examination results and the clinician’s experience play an extremely important role in determining the nature of thyroid nodules. Generally speaking, experienced clinicians can make a preliminary diagnosis based on the location, size, shape, echogenicity, presence or absence of a ring around the nodule, and the degree of blood flow signal of a thyroid nodule. For thyroid nodules with irregular borders, unclear circumference, incomplete envelope, uneven internal echogenicity or rough irregular calcifications, gravel-like strong echogenicity or hypoechogenicity, be alert to the possibility of malignancy. 4. Thyroid needle aspiration cytology: Thyroid needle aspiration cytology is performed by aspiration of tissue from the nodule site with a fine needle and smear. Needle aspiration cytology is currently the most effective way to determine the nature of thyroid nodules without surgery, and with the development of influential technology, ultrasound and CT-guided needle aspiration methods can now be used to make a pathological diagnosis for very small nodules. For early and smaller thyroid nodules needle aspiration is more difficult to operate and still relies on the clinician’s experience to make the diagnosis. 5. Thyroid radioactivity scan: When radioactive iodine enters the body, it can be concentrated in the functional thyroid tissue, using imaging instruments to specifically show the location, shape, size and distribution of radioactivity in the thyroid gland, and according to the state of thyroid nodule concentration function, nodules are classified as hot, warm, cool and cold nodules. Cold nodules, especially single cold nodules, should be alerted to the possibility of malignancy. The diagnostic value of this method is lower than that of ultrasonography, and the cost is relatively high, so it is not very common to carry out clinical application, and can only provide reference. 6, other tests: percutaneous thyroid imaging, thyroid lymph node imaging, CT, MRI also have some value in determining thyroid nodules. However, CT and MRI are expensive and have little diagnostic value, so they are less commonly used in clinical practice. In conclusion, when suffering from thyroid nodules, it is important to go to a regular hospital with a thyroid specialist to avoid delaying the condition and delaying follow-up treatment.