To analyze predictive factors for all-cause mortality, cardiovascular (CV) mortality, nonfatal CV events (CVE) in maintenance hemodialysis (MHD) patients, and to compare the effects of standard hemodialysis (HD) and online hemodiafiltration (HDF) on these factors and outcomes. A total of 333 MHD patients were prospectively followed up for 50?+/-?15 months and all-cause death, CV death and CVE were registered. At the baseline, demographic, clinical, and laboratory data of the whole population were recorded. Then, patients were stratified into two groups according to the dialysis modalities, HD (n?=?268) and HDF (n?=?65). At the end of 6th month, clinical and laboratory data were recorded again. The predictive factors at baseline for all-cause mortality, CV mortality, and CVE were analyzed by Cox regression. The effects of HD and HDF on these factors at the 6th month and long-term outcomes were compared by t-test and KaplanMeier method, respectively. Age, gender, left ventricular mass index (LVMI), aortic arch calcification score (AoACS), hemoglobin (Hb) <10?g/dL, and ferritin >500?ng/mL maintained independent associations with all-cause mortality. C-reactive protein (CRP), LVMI, AoACS, and Hb <10?g/dL were associated with CV mortality. Prior cardiovascular disease (CVD), AoACS and LVMI were independent predictors of nonfatal CVE. Higher body mass index (BMI), body weight, total serum cholesterol, Hb concentration, and lower CRP level, LVMI, and AoACS were found in patients on HDF at the end of the 6th month. Improved outcomes with longer survival time for all-cause mortality, CV mortality, and CVE were found in HDF group. Age, gender, LVMI, AoACS, Hb, and ferritin were predictors of all-cause mortality in MHD patients. CRP, LVMI, AoACS, and Hb were associated with CV mortality. Prior CVD, AoACS, and LVMI were independent predictors of nonfatal CVE. HDF could improve BMI, body weight, total serum cholesterol, Hb, CRP, LVMI, AoACS, and long-term outcomes, including all-cause mortality, CV mortality, and CVE.