Lung effusion in the elderly actually refers to the accumulation of fluid in the pleural cavity, which should be promptly examined in the hospital to clarify the cause of the effusion and take targeted treatment. Elderly pulmonary effusion is usually caused by a variety of causes, such as pneumonia, tuberculosis, lung cancer, etc. The cause of the disease should be clarified in a timely manner, and then take targeted treatment for the cause of the disease. If the cause cannot be clarified, it is usually necessary to take pressure-reducing treatment in time to pump out and drain the fluid in the chest cavity to alleviate the symptoms, and then clarify the cause according to the later development of the disease and special symptoms. If it is caused by malignant tumors, it is recommended to control the condition with adjuvant treatment of radiotherapy and chemotherapy. If the elderly have pulmonary effusion, they should maintain good living habits, avoid smoking and alcohol, and strengthen the nutrition of the diet to promote the improvement of the condition.