Abstract: Cold nodules are the common form of thyroid nodules in radionuclide imaging. Inflammation, cysts, tumors, hemorrhage and so on can be expressed as cold nodules. And, according to the statistics, an average of about 20% of the cold nodules are malignant. So accurate identification of nonfunctioning thyroid nodules not only contribute to the comprehensive nature of the detection of thyroid cancer, but also the right choice for the clinical treatment programs provide an important guide. At present, on the basis of kinds of different imaging agents, a number of methods to identify the nature of thyroid cold nodules were developed, and constantly perfected.