Objective To evaluate the effect and safety of double maintenance-dose clopidogrel on patients after percutaneous coronary intervention.Methods We searched CNKI,VIP,CBM,PubMed,EMBase,the Cochrane library database published article about double maintenance doses clopidogrel and 100 mg aspirin for PCI patients.The forest plot was drawn by RevMan 5.2,statistical software from the literature data and the funnel plot was also drawn to check the literature publication bias.Results A total of 12 Chinese papers were selected.Meta analysis results were as follows:Compared with 75 mg-maintenance dose,150 mg-maintenance dose reduced the rate of platelet aggregation [MD =-2.31,95％CI =(-2.98,-1.64),P＜0.05];in the treatment group and the control group,the incidences of major adverse cardiac events and minor adverse cardiac events were 3.93％ and 10.76％,with statistically significant difference (P ＜ 0.05);the incidences of major bleeding events were 1.56％ and 0.47％,without statistically significant difference (P ＞ 0.05);the incidences of non-major bleeding events were 7.40％ and 6.21％,and the difference was not statistically significant (P ＞ 0.05).Conclusion Compared with 75 mg-maintenance dose clopidogrel on patients after percutaneous coronary intervention,150 mg-maintenance dose exerted better inhibitory effect on platelet aggregation with a reduced incidence of major adverse cardiac events.Moreover,the incidences of major bleeding event risk and non-major bleeding events between the two doses showed no significant difference.