Lung cavities are mainly formed when lung tissues become necrotic due to lesions, and then the necrotic tissues are discharged from the bronchial tubes through drainage, and gas is inhaled. Lung cavitation is a manifestation of lung imaging, which can reflect some lesions in the lungs, and is commonly seen in infectious diseases such as pneumonia, tuberculosis, lung abscess, etc. Non-infectious factors such as peripheral bronchopulmonary carcinoma, lung metastases, pneumoconiosis, rheumatism, etc. can also be seen in lung cavitation. The symptoms of lung cavities caused by different diseases are different, and it is necessary to judge the disease according to the distribution location, size, shape and number of cavities. For example, tuberculosis lesions are mostly found in the posterior segment of the apices and the dorsal segment of the lower lobes of both lungs, and the size of the cavities varies, mostly favoring the side of the lung door. When the lung examination appears abnormal must seek medical help in time, under the guidance of the doctor to seek the cause of the disease, the cause of the treatment. Avoid delayed treatment, making the disease worse and causing more serious complications.