The main hazard of chest X-ray is that ionizing radiation penetrating human tissues will make the normal tissue cells of the human body may undergo gene mutation or chromosome breakage and other changes, thus triggering cancerous changes in tissue cells. The intensity of ionizing radiation of X-ray is within the national permissible range, and under normal circumstances, the radiation dose received in one chest X-ray will not cause great harm to the human body. However, frequent acceptance of chest X-ray examination will lead to an increase in the chances of cancerous changes in the cells of the patient’s body, which will easily lead to the occurrence of various neoplastic diseases, such as thyroid cancer, leukemia, and so on. Chest X-ray has special diagnostic value for lung disease, heart disease and bone fracture in clinic, which has the function of characterizing and locating the disease, and the results of chest X-ray examination can help doctors to better judge the patient’s disease condition, so as to give the patient the correct treatment measures. Therefore, patients who need chest X-ray examination should go to regular hospitals and use standardized instruments for chest X-ray examination to reduce the damage of ionizing radiation.