The survival time of patients with pulmonary effusion, i.e. pleural effusion, is related to the etiology and needs to be analyzed on a case-by-case basis and cannot be generalized. Pleural effusion caused by infectious diseases such as tuberculous pleurisy, subphrenic inflammation, lung abscess, lobar pneumonia, etc. can disappear after the inflammation is controlled and will not affect the patient’s life expectancy. Pleural effusion caused by malignant tumors of the lung and pleura, such as bronchopulmonary carcinoma and pleural mesothelioma, usually indicates the presence of metastasis of the tumor. Due to the rapid progress of malignant proliferative lesions and serious consumption of the body, patients have a shorter survival period, which is usually about six months or even shorter if they are old and frail. Pleural effusion caused by other diseases such as cardiac lesions and liver lesions needs to be treated actively. Patients with poorer and more serious conditions and uncontrollable pleural effusion can affect their respiratory function, and once combined with sudden triggers such as infection and fatigue, it can quickly lead to respiratory failure and death. Patients with pleural effusion should be promptly seen by the respiratory medicine department of the hospital to clarify the cause and then treat the symptoms.