Patients with bronchial dilatation can often cough up a large amount of purulent sputum, mostly because their bronchial walls are stimulated and damaged by acute and chronic inflammation, causing damage and disappearance of their ciliated cells. When mucus secretion increases, sputum cannot be discharged effectively, and at the same time, because the local lumen of the bronchus is deformed and enlarged, more secretions can accumulate in the lumen, causing patients to cough up a large amount of purulent sputum. Repeated chronic inflammatory stimulation causes the proliferation of cupped cells and mucous cells in the bronchial mucosa, so both types of cells can cause a significant increase in mucosal secretion, which can lead to an increase in the amount of sputum in patients. When respiratory tract infection occurs, it can stimulate the local inflammatory response of the bronchial mucosa and induce patients to produce large amounts of purulent sputum. For some patients with severe infection, they can cough up large amounts of purulent sputum and make their sputum stratified. Patients with bronchial dilatation should be given appropriate expectoration and postural drainage to allow better elimination of aspirated sputum, alleviate the degree of airway infection and reduce the clinical symptoms of the patient.