Most of the pleural effusion after lung surgery will take 2~4 weeks to fully recover, depending on the type of surgery, postoperative treatment and the patient’s physical condition. After surgery for common benign lesions, the amount of pleural effusion is relatively small and can be absorbed on its own, and the condition will gradually improve after 1~2 weeks, and the pleural effusion will be absorbed completely after 2~3 weeks. In case of lung cancer surgery or larger scope of surgery, the amount of postoperative pleural effusion is more, most of them need to place drainage, and the recovery time will be prolonged to 4 weeks. The recovery time is shortened when the patient is in good health. During the recovery period of pleural effusion, it is necessary to pay attention to closely observe the changes of the amount of fluid, if the amount of fluid and accompanied by the symptom of chest tightness, it is necessary to consult a doctor in time for observation and standardized treatment under the guidance of clinicians.