Symptoms of pleural effusion of lung cancer include chest tightness, breath-holding, shortness of breath after activity, dyspnea, dry cough, chest pain, lethargy, fever and so on. Chest tightness and breathlessness are relatively common symptoms in patients with pleural effusion of lung cancer. Generally, the severity of chest tightness and breathlessness is correlated with the amount of pleural effusion, the speed of its production and the function of the patient’s own lungs. The larger the amount of fluid, the faster it is produced, and the poorer the lung function, the more severe the chest tightness and breathlessness will be, and the more likely it is that the patient will have difficulty breathing, leading to respiratory failure. If the amount of pleural effusion is not large, it usually manifests as shortness of breath after activity, and some are accompanied by dry cough without sputum, and some have chest pain and other symptoms. Lung cancer pleural effusion, mostly suggests that the disease has developed to the advanced stage, and many patients have systemic symptoms such as emaciation and fever. Due to lack of oxygen, patients also have headache, dizziness and swelling. It is suggested that lung cancer patients should go to the hospital for consultation and active treatment in time, so as to avoid delaying their condition.