The pleural cavity consists of the wall layer of the pleura and the dirty layer, which are airtight potential cavities that do not contain air. When the pleura is broken for any reason and air enters the pleural cavity, it is called pneumothorax. At this time, the pressure in the pleural cavity rises, and even the negative pressure becomes positive pressure, which compresses the lungs and obstructs the venous blood flow back to the heart, producing different degrees of lung and heart dysfunction. Injecting filtered air into the pleural cavity by manual means in order to identify intrathoracic disease under X-ray is called artificial pneumothorax. Pneumothorax caused by thoracic trauma, needle treatment, etc. is called traumatic pneumothorax. The most common pneumothorax is caused by lung diseases that rupture the lung tissue and the dirty pleura, or the pulmonary blisters and tiny emphysematous vesicles near the lung surface rupture on their own, and the air in the lungs and bronchi escapes into the pleural cavity, called spontaneous pneumothorax. Primary pneumothorax is usually caused by congenital lung tissue hypoplasia and the presence of small pulmonary blisters or pulmonary blisters under the pleura after rupture, and the lesion is often located in the apical part of the lung; secondary pneumothorax is caused by the rupture of the pulmonary blisters under the pleura due to the original lung lesion or due to direct damage to the pleura by the lesion itself. Patients often have triggering factors such as holding heavy objects, breath-holding, strenuous exercise, etc., but there are also cases of pneumothorax occurring during sleep, where the patient suddenly feels chest pain, shortness of breath, breath-holding, and may have cough but little sputum. The principle of treatment lies in appropriate exhaustion according to the different types of pneumothorax, in order to release the obstacle generated by the pneumothorax on breathing and circulation, so that the lung can reopen as soon as possible and restore the function, and also to treat the complications and primary diseases.