ObjectiveTo systematically review the efficacy of coenzyme Q10 as adjuvant therapy for patients with heart failure. MethodsDatabases including PubMed, The Cochrane Library (Issue 7, 2015), EMbase, CBM, CNKI, WanFang Data and VIP were searched to collect randomized controlled trials (RCTs) about coenzyme Q10 in the treatment of heart failure from inception to June 2015. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed using RevMan 5.3 software. ResultsA total of 24 RCTs involving 2883 patients were included. The results of meta-analysis showed that:compared with the control group, the coenzyme Q10 group had the lower mortality (RR=0.62, 95%CI 0.47 to 0.83, P=0.001), higher eject fraction (EF) level (MD=3.81, 95%CI 1.22 to 6.40, P=0.004), lower NYHA cardiac function classification (MD=-0.31, 95%CI -0.35 to -0.26), P<0.00001), and higher exercise tolerance (SMD=0.70, 95%CI 0.31 to 1.09, P=0.0005). ConclusionCurrent evidence shows that, coenzyme Q10 can reduce mortality, NYHA cardiac function classification and improve EF and exercise tolerance in patients with heart failure. Due to the limited quality of included studies, the above conclusion still needs to be verified by more high quality studies.