Pneumothorax is a common disease in respiratory medicine, which is traditionally treated by pleural puncture and aspiration and closed drainage of the chest cavity. Today we introduce the application of fine catheter chest closed drainage in the treatment of pneumothorax through a case. Patient Chen, male, 75 years old, was diagnosed with right spontaneous pneumothorax in a hospital, and the affected lung could not be reopened by thoracentesis suction twice. After being transferred to our hospital, we used the method of closed chest drainage with fine catheter plus negative pressure suction to drain the gas in the chest cavity in less than two days, and the X-ray examination indicated that the lung was completely reopened, and the patient was extubated on the third day and discharged on the fourth day. This method solves the pain of many pneumothorax patients and shortens the hospital stay. This method has the following advantages: 1.Small trauma, almost no bleeding, small scars, shorten the treatment course. 2.The patient’s tube left in place after puncture does not affect activities such as turning over. 3.The use of negative pressure suction is slow and continuous, and generally does not cause diplopia pulmonary edema. 4.If not suctioned, it is very convenient to use heparin cap to pump air at any time.