The time to remove the drain from the chest cavity after lung nodule surgery is usually 2~3 days, but the exact removal time needs to be decided according to the patient’s condition, which is mainly related to the amount of drainage fluid and the presence of gas. Because there may be exudate oozing out of the wound after lung nodule surgery, and there may also be infection or pneumothorax formation, etc., it is necessary to place a drain to drain the pleural fluid and gas after lung nodule surgery, and the specific time for removing the drain in the clinic is about 2-3 days, but it is not always the same. If after 2~3 days, there is still more drainage fluid or gas bubbles coming out of the drainage tube, it is not recommended to remove the drainage tube too early, so as not to affect the healing of the wound with too much drainage fluid, and the observation of the drainage tube can be used to judge the internal condition of the incision, and the drainage tube can be removed when there is less than 50 ml of drainage fluid/day and no gas emission. The specific time for removing the drain is recommended to be determined by the attending physician according to the patient’s specific condition.