Thyroid nodules and thyroid cancer are frequent and common diseases of the endocrine system. The prevalence of thyroid nodules obtained by palpation is 37%, and the prevalence of thyroid nodules obtained by high-resolution ultrasound is 2076%. The prevalence of thyroid cancer among thyroid nodules is 515%. The prevalence of thyroid cancer in China has shown an increasing trend in recent years, and the rate of surgery for non-essential thyroid nodules has increased significantly. There is a lack of consensus and standardization in the surgical approach to thyroid cancer, radioiodine therapy, TSH suppression therapy and monitoring of thyroid cancer recurrence. The diagnosis and treatment of thyroid nodules and thyroid cancer involves several clinical disciplines such as endocrinology, head and neck surgery, general surgery, and nuclear medicine, and is a typical interdisciplinary disease. In order to standardize the diagnosis and treatment of thyroid nodules and thyroid cancer in China and improve the clinical cure rate, in April 2011, the Endocrinology Branch of the Chinese Medical Association, the General Surgery Branch of the Chinese Medical Association, the Head and Neck Tumor Specialty Committee of the Chinese Anti-Cancer Association, and the Nuclear Medicine Branch of the Chinese Medical Association decided to jointly compile the first “Guidelines for the Diagnosis and Treatment of Thyroid Nodules and Differentiated Thyroid Cancer” in China. The compilation work took one year, and 56 experts from four societies participated in the compilation and review work. Based on the principles of “based on national conditions, evidence-based, new and practical, and convergence while keeping differences”, the writing committee carefully summarized the practical experience of diagnosis and treatment of thyroid nodules and differentiated thyroid cancer in China, and fully drew on the essence of international guidelines and existing guidelines of various disciplines in China to compile this guideline, which is currently accepted and recognized by all four disciplines. This guideline is accepted by all four disciplines. This guideline includes two chapters on thyroid nodules and differentiated thyroid cancer, with 54 problematic articles and 72 recommended articles. The recommended articles indicate the strength of recommendation. The content includes the differentiation of benign and malignant thyroid nodules, determination of fine needle aspiration biopsy (FNAB) results, indications for surgical treatment of thyroid nodules; selection of thyroid surgery for differentiated thyroid cancer (DTC) and management of involved lymph nodes, TNM staging and risk of recurrence assessment, indications and specific methods for 131 iodine nail clearing therapy, 131 iodine clearing therapy for DTC metastases, DTC TSH suppression therapy for DTC, monitoring of serum Tg concentration for DTC recurrence, etc.