With the development of modern medicine, especially the active development and application of evidence-based medicine in China, medical imaging examinations are increasingly used in clinical practice. A large number of imaging examinations are bound to bring about a more positive development of clinical medicine; on the other hand, they are also bound to bring adverse consequences, which require sufficient awareness among medical workers and patients to avoid irreversible consequences. Radiology is the most important department of medical imaging, and its advantages and disadvantages are also very significant. The advantages are mainly as follows: 1, respiratory, circulatory, digestive, neurological, skeletal, urological, reproductive and other systemic diseases are almost always diagnosed by combining radiological examination, and even some diseases radiological examination is the only means to confirm the diagnosis. 2.The severity, course and stage of the disease are often provided by radiological examination, which can help in the selection of clinical treatment plan. 3, the efficacy and prognosis of the disease often need radiological examination to review the evidence. However, excessive or inappropriate radiological examinations can also bring adverse consequences, most commonly in the form of radiation damage and increased medical costs. Both physicians and patients should try to avoid these adverse consequences, and radiologists in particular have an even greater responsibility. To this end, the following points are recommended, which may be helpful: 1, diseases that can be examined by other imaging means (such as ultrasound, infrared, etc.), should be used as little as possible or even not to use radiological examination. 2, diseases that can be diagnosed with X-ray plain film or magnetic resonance examination, CT examination should be avoided as much as possible. 3, CT examination after a more accurate diagnosis and can be reviewed by X-ray plain film disease, should try to use plain film and avoid CT examination. 4, physical examination or long-term CT review of the disease, the examination as far as possible with low-dose CT. 5, radiological examination should try to the patient’s sensitive parts and family members to carry out the necessary radiation protection! 6, pregnant women and infants should pay particular attention to radiation protection, it is best to avoid radiological examinations, such as must be examined, patients or family members should consult the radiology department of medical workers or radiation management workers of the Institute of Occupational Safety and Health, and make a trade-off between the pros and cons before making radiological examinations.