ObjectiveTo systematically review clinical efficacy and safety of bone marrow stem cells transplantation in treating primary dilated cardiomyopathy (DCM). MethodsSuch databases as PubMed, CENTRAL, EMbase, Web of Knowledge, VIP, CNKI, CBM and WanFang Data were searched from inception to March 2014 for the randomized controlled trials (RCTs) about bone marrow stem cells transplantation for DCM. According to the inclusion and exclusion criteria, two reviewers independently screened literature, extracted data, and assessed methodological quality of included studies. Then meta-analysis was performed using RevMan 5.2.0 software. ResultsA total of ten RCTs involving 374 patients were included. The results of meta-analysis showed that, a) for safety, after 3 months there was no significant difference in the incidence of malignant arrhythmia events between bone marrow stem cell transplantation group and routine treatment group (RR=0.81, 95%CI 0.38 to 1.72, P=0.58); and b) for efficacy, compared with the control group, left ventricular ejection fraction (LVEF) increased in the bone marrow stem cell transplantation group after 3 months (WMD=3.86, 95% CI 2.53 to 5.20, P<0.000 01) and after 6 months (WMD=5.54, 95%CI 3.02 to 8.06, P<0.000 1). The bone marrow stem cell transplantation group were better in increased 6-minute walking distance after 3 months (WMD=22.12, 95%CI 7.78 to 36.46, P=0.003), increased 6-minute walking distance after 6 months (WMD=102.79, 95%CI 50.16 to 155.41, P=0.000 1), decreased perfusion defect of myocardium percentage after 3 months (WMD=-4.00, 95%CI -5.87 to -2.13, P<0.000 1). However, there was no significant difference in left ventricular end-diastolic diameter (LVEDD) between two groups after 3 months (WMD=-0.37, 95%CI -1.67 to 0.93, P=0.57) and after 6 months (WMD=-0.70, 95%CI -2.76 to 1.36, P=0.51). ConclusionBone marrow stem cells transplantation for dilated cardiomyopathy is effective in improve patients' heart function with good safety, with significant difference. Due to limited quantity and quality of the included studies, more high quality and large-scale RCTs are needed to verify the above conclusion.