The severity of pneumothorax symptoms depends on the speed of onset, the degree of lung compression and the condition of primary lung disease, the typical symptoms are sudden onset of chest pain, followed by chest tightness and dyspnea, and there may be irritating cough, this chest pain is often needle-like or knife-like, and the duration is very short, the irritating dry cough is caused by gas irritation of the pleura, most of the patients with rapid onset, large pneumothorax volume, or with the original lung lesion, then shortness of breath is obvious, some Most of the patients have pneumothorax with sudden onset, large amount of pneumothorax, or with pre-existing lung lesions, the shortness of breath is obvious, some of them have violent cough, forceful breath-holding stool or heavy lifting before the onset of pneumothorax, but many of them have onset during normal activities or quiet rest, young healthy people with moderate amount of pneumothorax rarely have discomfort, sometimes patients are only found during physical examination or routine chest fluoroscopy, while elderly people with emphysema, even if the lung compression is less than 10%, can also produce obvious dyspnea. COPD (chronic obstructive pulmonary disease) is the most common disease in patients with secondary pneumothorax, and it is important to be aware of these patients and treat them aggressively because they are less tolerant of pneumothorax. Trials have shown that in patients with pneumothorax over the age of 50, as in patients with pre-existing lung disease, treatment with simple suctioning is often ineffective. Therefore, primary pneumothorax over the age of 50 should be treated as equivalent to secondary pneumothorax when considering treatment options. Another factor to consider is the presence or absence of dyspnea. The rate of natural absorption of gas from the chest cavity is 1.25% to 2.2% of the hemithorax per 24h. Therefore, it takes more than 6 weeks after a pneumothorax if it is allowed to absorb naturally, and this time can be longer if there is a gas leak. The treatment of pneumothorax is aimed at promoting the reopening of the affected lung, eliminating the cause of the disease and reducing recurrence. X-ray is an important method to diagnose pneumothorax. If there is a high clinical suspicion of pneumothorax and the posterior anterior chest radiograph is normal, a lateral chest radiograph or lateral recumbent chest radiograph should be performed. Most of the pneumothorax chest films have clear pneumothorax line, which is the junction line between the atrophied lung tissue and the gas in the pleural cavity, showing the convex line shadow, and the pneumothorax line is a translucent area without lung texture outside, and the compressed lung tissue inside the line. The mediastinum and heart can be displaced to the healthy side when there is a large amount of pneumothorax. In the case of combined pleural effusion, the pneumothorax surface can be seen. The diagnosis of restricted pneumothorax is easily missed during posterior-anterior X-ray examination, and lateral chest radiographs can assist in the diagnosis. A mediastinal emphysema should be considered if there is a transilluminated band around the parietal border of the heart. CT is more sensitive and accurate than X-ray chest radiograph for the differentiation of small pneumothorax, limited pneumothorax, and pneumomediastinum from pneumothorax. The basic CT manifestation of pneumothorax is the appearance of extremely low-density gas shadow in the pleural cavity, accompanied by different degrees of compression and atrophy changes of lung tissue. Spontaneous pneumothorax is one of the common clinical emergencies, which often affects work and daily life if not treated in time, especially in patients with persistent or recurrent pneumothorax, which often damages lung function or even threatens life if not treated timely or appropriately. Therefore, it is very important to actively treat and prevent recurrence. In determining the treatment plan, the symptoms, signs, X-ray changes (degree of lung compression, presence of mediastinal shift), intrapleural pressure, presence of pleural effusion, speed of pneumothorax and original lung function status, first onset or recurrence, and other factors should be considered. The basic treatment principles include general treatment of bed rest, exhaustion therapy, recurrence prevention measures, surgical treatment and prevention and treatment of primary diseases and complications.