Pulmonary cavitation is an imaging term that refers to images formed when tissue in the lung is drained by draining bronchi after necrosis due to disease, and then gas is inhaled after the drainage. Images of cavities in the lungs are commonly seen in tuberculosis, lung abscess, lung cancer and, less commonly, in pulmonary cyst co-infection, pulmonary isolation, pulmonary encapsulation disease, and Staphylococcus aureus infection. The cause of cavitation can be identified clinically based on the site and size of the cavity. In terms of location, tuberculous cavities are more likely to occur in the posterior apical segment of the upper lobe and the dorsal segment of the lower lobe; cancerous cavities can occur anywhere in the lung field; lung abscesses are more common in the posterior segment of the upper lobe, the dorsal segment of the lower lobe and the basal segments; fungal disease occurs mostly in the middle and lower lung fields; pulmonary isolation disease occurs mostly in the posterior basal segment of the lower lobe; and encapsulated cysts are more common in the lower right side. In terms of size, tuberculous cavities are mostly 2-3 cm in diameter; cancerous cavities are more than 3 cm in diameter, lung abscess cavities vary in size, and most lung cyst cavities are 3 to 5 cm, and large ones can reach 10 cm or more. Pulmonary cavitation is a manifestation of imaging after disease. There are various diseases that can lead to pulmonary cavitation images, such as lung cancer, tuberculosis, lung abscess, lung cyst, pulmonary isolation disease, and Staphylococcus aureus infection. Pulmonary cavitation is found as soon as possible to clarify the cause and treat it as early as possible to avoid aggravation.