ObjectiveTo systematically review the association between the IL-6 gene -634G/C polymorphism and the risk of lung cancer. MethodsDatabases including the PubMed, EMbase, CNKI and WanFang Data were searched from inception to October 2015 to collect case-control studies about the correlation between the IL-6 gene -634G/C polymorphism and the risk of lung cancer. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed by using RevMan 5.3 software. ResultsA total of 12 case-control studies concerning 3 657 lung cancer cases and 4 100 controls from 11 articles were included. The results of meta-analysis showed that there was no significant association between the -634G/C polymorphism and the risk of lung cancer (GG+GC vs. CC: OR=1.11, 95%CI 0.89 to 1.39, P=0.37; GG vs. CC+GC: OR=1.17, 95%CI 0.88 to 1.55, P=0.27; GG vs. CC: OR=1.27, 95%CI 0.93 to 1.72, P=0.13; GC vs. CC: OR=1.12, 95%CI 0.89 to 1.40, P=0.33; G vs. C: OR=1.08, 95%CI 0.89 to 1.30, P=0.43). ConclusionIL-6 gene -634G/C polymorphism may not be a risk factor of lung cancer. Due to the limited quality and quantity of included studies, more high quality studies are needed to verify the above conclusion.