Multiple nodular shadows in both lungs are round or circular shadows of increased density that can be seen on chest radiographs or CT lung films, called multiple nodular shadows in both lungs. Multiple nodular shadows are caused by lung infections, but they can also be caused by pulmonary nodular disease, tuberculosis, old lesions, and, rarely, malignant lung tumors. If the nodules are caused by a lung infection, they should be reviewed after two weeks of anti-infection. If there is no change, the lung CT should be done regularly, for example, at three months, and if there is still no change, the lung CT should be done again in six months, and if there is still no change, the lung CT should be followed up under the guidance of the doctor. If there are nodules, uneven density, or pleural depression, lobar, vacuolation, or vascular signs during the follow-up, malignancy has occurred. In this case, further diagnosis and treatment are necessary as soon as possible.