Four years after lung cancer surgery, the cough may be caused by recurrence of disease, bronchopneumonia, etc. Specific treatments need to be carried out according to the causes of disease. 1. Recurrence of disease: If the disease recurs and causes coughing symptoms, targeted drugs, chemotherapy and radiotherapy can be chosen according to the patient’s own condition. If it is a single relapse and the patient’s own physical condition is good, open thoracic or thoracoscopic surgery can be carried out for treatment. 2. Bronchopneumonia: After lung cancer surgery, if the patient’s physical condition is poor, bronchopneumonia can cause coughing symptom, which can be treated with drugs such as cefadroxil slow-release capsules, cefaclor slow-release tablets, minocycline hydrochloride capsules, etc. It is recommended to go to the hospital for lung cancer surgery in time. It is recommended to go to the hospital in time for CT examination of the lungs, to clarify the cause of the disease, and to carry out targeted treatment as soon as possible. Drugs need to be used under the guidance of a doctor, avoid self-medication.