Chest X-rays can be taken more than once a year. However, if it is not necessary, it is recommended to take a chest X-ray once a year, which is safer. Chest X-ray has a certain amount of radiation, although the dose of radiation is not large, but still has a certain impact on health, once a year to take a chest X-ray is a relatively safe choice. If you can replace the chest X-ray with other examination methods, you should not take chest X-ray if you can. Some patients, due to the need of their condition, must take chest X-ray to determine the severity of their condition, assess and analyze the disease and treatment effect, etc., and may need to take chest X-ray several times in a short period of time as the basis for diagnosis, assessment and treatment. In this case, the advantages of chest radiography outweigh the disadvantages. If it is not necessary to take chest radiographs, you should avoid taking chest radiographs as much as possible, and it is better to choose other examination methods instead.