Postoperative cough after thymic cyst surgery is considered to be caused by local irritation and lung infection. 1. Local stimulation: when performing thymic cyst removal surgery, it may stimulate the surrounding tissues, such as injuring the bronchial tube, or retained closed chest drainage tube stimulation of the local area can appear postoperative cough, generally do not need special treatment, and in severe cases, you can take cough suppressant drugs, can control the symptoms. 2. Lung infection: when fever, cough, sputum and other symptoms occur in thymic cyst surgery, it is considered to be caused by lung infection, which can be treated by anti-infection therapy (e.g., levofloxacin, amoxicillin), and the symptoms are usually relieved after treatment. 3. Others: Due to surgical stimulation of subglottic nerve, phrenic nerve, etc., the nerve may conduct signals to pharyngeal muscle, respiratory muscle, etc. after surgery, causing coughing action. Coughing after thymic cyst surgery may also be related to other causes, it is recommended to perform relevant examinations to clarify the causes and standardize the treatment under the guidance of the doctor. In addition, the drugs involved in the above should also be used under the guidance of a doctor.