Abstract: OBJECTIVE To explore the risk factors for chest infections in patients undergoing pneumothorax closed drainage and put forward the countermeasures so as to reduce the infection rate. METHODS A total of 186 patients who underwent the pneumothorax closed drainage in the hospital from May 2011 to Jun 2013 were enrolled in the study, then the risk factors for postoperative chest infections in the patients were analyzed, the multivariate logistic regression analysis was carried out, the levels of leukocytes and protein quantification in pleural fluid as well as white blood cells and neutrophils in blood were observed before and after the treatment, the treatment countermeasures were put forward, and the statistical analysis of data was performed with the use of SPSS 16.0 software. RESULTS Of the 186 patients, 16 had chest infections, with the infection rate 8.60%. Totally 16 strains of pathogens were isolated, of which 31.25% were Pseudomonas aeruginosa, and 25.00% were Staphylococcus aureus. The multivariate logistic analysis showed that the risk factors for the chest infections in the patients undergoing the pneumothorax closed drainage included the no less than 60 years of age, complication with chronic pulmonary disease and diabetic mellitus, spread of primary pulmonary lesions, more than 3 days of drainage indwelling, and prophylactic use of antibiotics (P<0.05). There was significant difference in the level of leukocytes, protein in pleural fluid or white blood cells, neutrophils in blood before and after the treatment (P<0.05). CONCLUSION There is a variety of risk factors for the postoperative chest infections in the patients undergoing the pneumothorax closed drainage. It is necessary to strengthen the infection management so as to reduce the infection rate.