Background Increased red blood cell distribution width （RDW） is associated with adverse outcomes in patients with heart failure （HF）. The objective of this study was to compare the differences in the predictive value of RDW in patients with HF due to different causes. Methods We retrospectively investigated 1,021 HF patients from October 2009 to December 2011 at Fuwai Hospital （Beijing, China）. HF in these patients was caused by three diseases; coronary heart disease （CHD）, dilated cardiomyopathy （DCM） and valvular heart disease （VHD）. Patients were followed-up for 21 ~ 9 months. Results The RDW, mortality and survival duration were significantly different among the three groups. Kaplan-Meier analysis showed that the cumulative survival decreased significantly with increased RDW in patients with HF caused by CHD and DCM, but not in those with HF patients caused by VHD. In a multivariable model, RDW was identified as an independent predictor for the mortality of HF patients with CHD （P 〈 0.001, HR 1.315, 95% CI 1.122-1.543）. The group with higher N-terminal pro-brain natriuretic peptide （NT-proBNP） and higher RDW than median had the lowest cumulative survival in patients with HF due to CHD, but not in patients with HF due to DCM. Conclusions RDW is a prognostic indicator for patients with HF caused by CHD and DCM; thus, RDW adds important information to NT-proBNP in CHD caused HF patients.