To determine whether statin therapy improves survival in patients with heart failure (HF) secondary to nonischemic dilated cardiomyopathy (non-IDC), data from 1,024 patients with non-IDC (New York Heart Association functional class III and IV HF) and left ventricular ejection fraction < or =0.35 who were enrolled in the BEST were analyzed. The association of statin therapy at the initial screening visit with all-cause and cardiovascular mortality was evaluated using multivariate Cox proportional hazards models. After adjusting for age, gender, race, systolic blood pressure, total cholesterol, New York Heart Association functional class IV, estimated glomerular filtration rate, current cigarette smoking, left ventricular ejection fraction, angiotensin-converting enzyme inhibitor use, antiplatelet therapy, diabetes mellitus, treatment group (beta blocker or placebo), and hypertension, statin use was independently associated with decreased all-cause mortality (hazard ratio 0.38, confidence interval 0.18 to 0.82, p = 0.0134) and also with decreased cardiovascular death (hazard ratio 0.42, confidence interval 0.18 to 0.95, p = 0.037). In conclusion, in patients with moderate or severe HF due to non-IDC entered into BEST, statin therapy at entry was independently associated with a decrease in all-cause and cardiovascular mortality.