Nuclear medicine is a discipline that studies the application of nuclear technology in medicine and its theory, and is an important part of modern medicine. The formation of the discipline of nuclear medicine not only represents the level of development of nuclear technology, a cutting-edge technology, but also its development has been continuously integrated with the fruitful results of related advanced technologies and constantly improved and enriched. Nowadays, nuclear medicine has penetrated into all fields of medicine and has been applied more and more widely, becoming an important tool for disease diagnosis, treatment and medical research. Nuclear medicine is further divided into clinical nuclear medicine, experimental nuclear medicine and nuclear pharmacology. As clinical nuclear medicine, its nuclide imaging has become an important part of modern medical imaging technology, which has outstanding advantages in reflecting the physiological and biochemical processes of organs or tissues, systemic and local metabolism, blood flow and functional changes, especially in obtaining information on molecular-level changes of diseases, providing sensitive, specific, simple and safe diagnostic tools for clinical practice, and thus has become an important tool for early diagnosis of diseases, guiding treatment, judging efficacy and estimating prognosis. Therefore, it has become a powerful tool for early diagnosis of diseases, guiding treatment, judging efficacy and estimating prognosis. Nuclear myocardial imaging can not only diagnose coronary heart disease non-invasively, but also become an important basis for determining the survival of myocardial cells in patients with myocardial infarction and deciding whether to perform hemodynamic reconstruction. The 2005 Nobel Prize in Physiology and Medicine was awarded to the two Australian scientists who discovered that Helicobacter pylori can cause gastric disease, and that nuclear medicine can detect the presence of this bacterium in people with gastric disease with a single breath using the 14-carbon labeling method. This makes it easier to detect gastric disease. Meanwhile, radionuclide therapy is an effective means of non-invasive treatment for certain diseases. 131 iodine for hyperthyroidism is superior to other methods, and radionuclide therapy has a significant pain relief effect on pain caused by advanced bone metastases of tumors. The efficacy of radionuclide patching in the treatment of pediatric capillary hemangioma, hyperplastic scar, certain skin diseases and eye diseases has also been recognized. Furthermore, in vitro immunoassay, a test method that won the 1977 Nobel Prize in Biomedicine, provides reliable data on clinical diseases and scientific research and is the gold standard for other tests. Now, more than 1,000 hospitals have set up nuclear medicine departments, and more than 40 SPECT (or SPECT/CT) and 8 PET (or PET/CT) have been installed and used in Shandong Province alone. Experts predict that in the 21st century, nuclear medicine will play a more important role in the field of life sciences.