The causes of 125 pneumothorax which is confirmed by roentgenological, surgical and pathological findings werepulmonary Tb. 50(40%) ; blunt injury, 24(19.2%) ; stab injury, 16(12.8%) ; tumor, pulmonary paragonimiasis, each 1(0.8%) with order in frequency. Pneumothorax developed more frequently in the male, the ratio being 4.7:1 and ismost common in third and fourth decades. The site distribution of pneumothorax was 63 patents in right, 48 in leftand 14 in both side. Pneumothorax is caused by pulmonary tuberculosis was 15 patients who did not know until ithad developed.