It is difficult to rely on what you eat to get rid of fluid in the pleural cavity; it can only be drained out by puncture and aspiration or continuous closed pleural drainage. Pleural effusion is due to a variety of reasons for the accumulation of excessive pathological fluid in the pleural cavity, which can not be effectively absorbed by itself. A small amount of pleural effusion can be left untreated, but it requires an intensive diet and treatment for causes such as heart failure due to various heart diseases, hypoproteinemia, constrictive pericarditis, pleurisy, and lung cancer. For moderate to large amount of pleural effusion, while treating the cause of the disease, in order to alleviate the symptoms of dyspnea and chest tightness caused by excessive effusion and to avoid infection, it is necessary to drain the excessive effusion, which is usually treated by thoracentesis and aspiration of fluid or closed drainage of the thoracic cavity, and also by strengthening nutrition, which will help the recovery.