Objective To evaluate the effect of online hemodiafiltration(OL-HDF)in the survival rate of maintenance hemodilysis(MHD) patients.Methods Randomized controlled trials(RCT),prospective controlled trials(PCT) and prospective cohort trials studying the effect of OL-HDF on survival rate of MHD patients were searched in the Pubmed /Medline, EMBASE、and Cochrane Library electronic databases, then the odds ratio was calculated. Results 5009 patients were included in this study: the effect of survival rate was compared in the OL-HDF and HD group. Compared with the HD group, the survival rate of OL-HDF group wasn not improved (Fixed effect model, OR=0.53,Z=5.51,P<0.00001,I2=38%). The subgroup of OL-HDF patients treated with a high substitution volume per session had better overall mortality compared with the HD group. There were no significant difference of overall mortality rate between low volume OL-HDF group and HD group（OR=1.0,Z=0.01,P=0.99,I2=0%）. Conclusions High volume OL-HDF may not improve the survival rate of MHD patients, associated with OL-HDF substitution volume.