A normal person will not have a nodular lung shadow. Many lung lesions can show up as nodule-like changes on imaging. Shadows that are less than 3 cm in diameter, have a well-defined morphologic structure and have certain morphologic features are clinically referred to as pulmonary nodular shadow. Most of them are benign lesions due to inflammation in the lungs, and after the inflammation disappears or is cured, the lungs become fibrotic and form calcified foci, thus causing nodular shadowing in the lungs; shadows can also be produced in the lungs of long-term smokers. In addition, lung tumors can also manifest as nodular shadow in the lungs. Pulmonary nodular shadow is an abnormal condition, and it is recommended to go to the hospital respiratory department for relevant examination. In life, pay more attention to rest, develop good eating habits, prohibit spicy and stimulating food, eat a light diet, eat fruits and vegetables, and take more vitamins.