Objective To systemically evaluate the the role of statins in prevention and treatment of community-acquired pneumonia (CAP). Methods A computer-based searching was conducted in PubMed,EMbase,Cochrane Library,Wanfang,and CNKI database up to October 2016. Totally 21 eligible articles were retrieved. According to the Cochrane Handbook 5.0 or Newcastle-Ottawa Scale (NOS) quality evaluation criteria,two independent reviewers carried out literature screening,data retraction,and quality evaluation. Meta-analysis was conducted with RevMan 5.3 software. Results A total 1 007 765 CAP patients from 12 studies were divided into two groups:statin group (n=118 096) and non-statin group (n=889 669). Meta-analysis suggested that statin use was associated with decreased mortality of CAP (OR=0.67,95%CI:0.57-0.79). We further divided the studies into North America group and Europe group and found the heterogenicity of North America group was lower than that of Europe group,and the Meta-analysis of both group supported the association of statin use with decreased CAP mortality (OR=0.66,95%CI:0.62-0.67;OR=0.71,95%CI:0.55-0.92). To identify the effect of statin use on mechanical ventilation,we included three articles (n=123 645) for further analysis (statin group,n=23 796;non-statin group,n=99 849),and Meta-analysis suggested that statin use was associated with decreased requirement for mechanical ventilation (OR=0.74,95%CI:0.70-0.78). Four articles (n=127 060) were enrolled (statin group,n=24 121 and non-statin group,n=102 939) to analyze the effect of statin use on ICU admission,and Meta-analysis suggested that statin use was associated with decreased requirement for ICU admission (OR=0.85,95%CI:0.82-0.88). Eleven articles (n=2 124 849) (statin group,n=306 108;non-statin group,n=1 818 741) to evaluate the effect of statin use on risk of CAP,and Meta-analysis suggested that long-term use of statins decreased the risk of CAP,although there was no statistical difference (OR=0.85,95%CI:0.85-1.07); the above studies were divided into case-control studies and cohort studies,and the case-control studies revealed statins increased the risk of CAP (OR=1.12,95%CI:1.03-1.21),while the cohort studies supported the association of statin use with decreased CAP risk (OR=0.46,95%CI:0.44-0.49). Conclusions Statin use may decrease the CAP mortality and the requirement for mechanical ventilation or ICU admission. However,whether statin use can reduce the risk of pneumonia remains unclear.