Pulmonary alveoli are found during chest CT examinations and are referred to as alveoli when there is a cyst-like structure at the lung apex and there is no lung texture in the cavity, which is generally considered to be gas in the cavity. Most of the alveoli are formed due to smoking or previous lung infections or tuberculosis, and some patients have structural abnormalities due to congenital developmental abnormalities. Pulmonary alveoli generally do not need to be treated, but only when they rupture and cause pneumothorax, usually pay attention to avoid strenuous exercise, it is best to quit smoking.