The traditional treatment of thyroid nodules is surgical excision. Image guided percutaneous radiofrequency ablation technology is a new method of tumor treatment carried out at home and abroad in recent years. This technology is based on implanting water-cooled ablation electrodes into the lesion under ultrasound guidance, causing coagulative necrosis of the lesion tissue through high temperature heating, and finally the necrotic tissue is absorbed by the body, thus achieving the purpose of minimally invasive local inactivation of the lesion. Ultrasound-guided radiofrequency ablation for thyroid nodules is a safe and effective method. This technique was pioneered and reported by Dr. Baek in Korea, and the final lesion absorption rate was 84.11±14.93% with no serious complications. It was confirmed that radiofrequency ablation is a safe and effective method to treat thyroid nodules. Currently, the most advanced RF ablation equipment has two ablation modes for thyroid nodules, namely MovingShot mode and fixed ablation mode, which can move the electrode while ablating and avoid harming the important organs around the thyroid gland in the neck while treating nodules. It is the most advanced technology in the world. Our department has been equipped with this technology one and a half years ago, the earliest in China, and so far we have treated more than 200 cases of large thyroid nodules over 2cm with 100% efficiency by using this most advanced technology. (1) Benign thyroid nodules that meet the following conditions: (1) nodules larger than 2 cm in diameter or nodules found to be enlarged during follow-up; (2) subjective symptoms, such as neck discomfort or pain, breathing or swallowing difficulties; (3) aesthetic needs; (4) thyroid nodules that cause a heavy psychological burden; 5. poor general condition that cannot tolerate surgery or refuses surgery. (2) For patients with recurrent thyroid malignant tumors who have lost the opportunity of re-operation, radiotherapy and chemotherapy, ablation can be used to destroy the lesions to achieve the purpose of tumor elimination or reduction, thus improving the quality of life and prolonging the survival of patients. The recurrence of metastasis in the cervical lymph nodes after clearance surgery. Contraindications (1) Coagulation mechanism disorders, serious bleeding tendency, and serious cardiopulmonary diseases that cannot tolerate the treatment are still considered as contraindications. (2) Relative contraindications: (1) nodules less than 2 cm; (2) follicular or malignant tumors on puncture biopsy; (3) highly malignant on ultrasound sonogram despite benign biopsy results (longer diameter than wide diameter, significant hypoechogenicity, microcalcifications inside, unclear borders, etc.); single malignant lesions (early papillary carcinoma) without lymph node metastasis on imaging. Preoperative preparation 1. Imaging examination: ultrasound or ultrasonography, etc. To understand in detail the location, shape, size, blood supply inside and around the nodule and the relationship between the nodule and the surrounding structures, and to determine the best needle site and route. 2. Other examinations: chest X-ray and electrocardiogram. Echocardiography, 24-hour ambulatory electrocardiogram, pulmonary function and laryngoscopy should be performed for combined cardiopulmonary diseases. 3.Blood test: serum four items, coagulation function, thyroid function, serum calcitonin, etc. 4.Puncture biopsy. Ultrasound-guided fine-needle aspiration or coarse-needle aspiration biopsy is required to clarify the diagnosis before surgery. 5.Sign the informed consent for surgery. Follow the principle of informed consent, explain the condition to the patient or family before treatment and introduce the significance of radiofrequency treatment and the possible complications during and after treatment and their countermeasures. 6.For those who have bleeding tendency, use vitamin K or Lizhixue before and after the operation. The common complications are: 1. Burning sensation and pain in the neck: a common complication, sometimes radiating to the head, teeth, shoulders and chest, usually appearing during the operation and relieved immediately by reducing the power or discontinuing the treatment. 2, fever: rare, mainly the body’s reaction to radiofrequency high temperature fever and the absorption of necrotic tissue fever, symptomatic treatment can subside. 3, extra-thyroidal hematoma: early incidence of about 2.1%, mostly disappears within 1 month. No bleeding or hematoma has occurred since we adopted the most advanced international radiofrequency machine and puncture concept a year and a half ago. 4.Returning laryngeal nerve injury: a more serious complication, the general incidence of about 1.3%. Our department adopts the most advanced international radiofrequency ablation instrument, and has exclusive water-cooled circulation technology for thyroid ablation design, and avoids the occurrence of nerve injury to the greatest extent by splitting ablation when necessary. 5.Thyroid function abnormalities: rare and mild, no need for medication, usually found in a week, and normalized after January. 6.Other complications: rare, such as infection, important structural damage (including the skin of the larynx, trachea, esophagus, blood vessels, etc.).