ObjectiveTo systematically evaluate the effects of closed drainage and simply closed drainage combined with pleurodesis in the treatment spontaneous pneumothorax. MethodsWe searched PubMed, Web of Science, The Cochrane Library, CBM, WanFang Data and CNKI from their inception to December 2nd, 2014, to collect randomized controlled trials (RCTs) of simple closed drainage versus closed drainage combined with pleurodesis in the treatment of spontaneous pneumothorax. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data and evaluated the risk of bias of included studies. Then, RevMan 5.3 software was used for meta-analysis. ResultsA total of 5 RCTs including 499 patients were included. The results of meta-analysis showed that:Compared with the simple closed drainage, the closed drainage combined with pleurodesis was superior in the effective rate of recurrence spontaneous pneumothorax (OR=6.85, 95%CI 3.26 to 14.39, P<0.000 01) and the recurrence rate of primary spontaneous pneumothorax (OR=0.32, 95%CI 0.18 to 0.57, P<0.001). But there were no statistical differences in both groups in the effective rate of primary spontaneous pneumothorax (OR=1.49, 95%CI 0.71 to 3.14, P=0.29), the hospital stays of primary spontaneous pneumothorax (SMD=0.08, 95%CI -0.16 to 0.31, P=0.52), the hospital stays of recurrence spontaneous pneumothorax (SMD=-1.67, 95%CI -3.96 to 0.61, P=0.15), and the duration of drainage of primary spontaneous pneumothorax (SMD=-0.11, 95%CI 0.79 to 0.58, P=0.76). ConclusionCurrent evidence suggests that closed drainage combined with pleurodesis could improve the effective rate of recurrence spontaneous pneumothorax and decrease the recurrence rate of primary spontaneous pneumothorax. Due to limited quantity and quality of included studies, the above conclusion should be validated by more high quality studies.