Blood sputum after lung surgery is a normal phenomenon, and there is no need to worry too much. During surgery, it is inevitable to cause trauma to the capillaries or small arteries of the lungs, and the damaged blood vessels will reach the fine bronchial tubes and bronchioles of the lungs after hemorrhage, so there will be blood in sputum, and the blood in sputum is usually dark blood, which is a normal phenomenon. It is also possible that tracheal intubation may cause bleeding due to damage to the larynx and airway, and blood sputum may appear after the operation, which can be recovered by itself in a short period of time, which is also a normal phenomenon. It is recommended to observe more and follow the doctor’s instructions to go to the hospital for regular checkups. If blood sputum persists after surgery, patients should go to the hospital for examination in time to find out whether there are infectious lesions or metastasis of cancer cells. During the recovery period, patients should pay more attention to rest and avoid overwork; maintain good mood; strengthen their nutrition in diet, focusing on light and nutritious food; forbid spicy and stimulating food, and quit smoking and drinking.