Traditionally symptomatic or large pneumothorax has been treated with a large-bore922-32F) chest tube and hospitalization. But pain and other significant complications may occur because of its large size and blind approach. Recently, with smally lumen catheter(6-10F), drainage of pleural effusion or empyema and decompression of pneumothorax resulting from percutaneous lung biopsy have been attempted. The authors used 8F catheter with suction apparatus to decompres 7 pneumothorax (6 spontaneous pneumothorax and 1 iatrogenic hemopneumothorax) under fluoroscopic guidance and the results were successful in all cases. it offers several advantages over traditional closed thoracotomy as follows : 1) Easier to insert and expeditious, 2) Fewer complications, 3) Less traumatic, 4) Less discomfort to the patient, 5) No scar formation in chest wall, 6) in case of pneumothorax during transthoracic needle biopsy, it provides immediate decompression and allows the lung biopsy to be continue , and 7) in case of connection with Heimlich valve, it can be managed on outpatient basis that lead to decreased hospital costs. We believe that small lumen catheter thoracostomy may become 1st choice of treatment modality in pneumothorax as safe and effective method.