BACKGROUND: Hypercholesterolemia is a major risk factor for incident coronary artery disease, mortality, and prevalence of heart failure (HF). However, patients with advanced HF often have low cholesterol, which is associated with a paradoxical poor prognosis. The relationship between lipid levels and outcomes in the patient with acute HF has not been studied in Korea. This study investigates the relationship between cholesterol levels and short- and long-term mortality in patients hospitalized with acute HF. METHODS: We analyzed a cohort of 3,200 patients with HF. Total cholesterol level (TC) was measured at the time of admission in 2,797 patients. Patients were stratified into quartiles of TC (Q1 <131, Q2 132-158, Q3 159-189, and Q4 >190 mg/dL). RESULTS: The cohort was 1,413 (50.5%) male, mean age was 67.6짹14.0 years, and LVEF was 38.6짹15.8%. Patients with lower serum TC had lower blood pressure, lower hemoglobiun, and higher cardiac natriuretic peptide level. Low TC was associated with increased risk of 1-year all-cause mortality (24%, 20%, 15%, 14% for Q1-Q4 respectively, P < .0001) as well as long-term all-cause mortality (69%, 29%, 22%, 20% for Q1-Q4 respectively, P < 0.001). On multivariate analysis, adjusting for multiple HF prognostic factors, low TC proved to be an independent predictor of worse outcomes, with hazard ratios for all-cause mortality of 1.163 (95% C.I.;1.085-1.227, p<0.001). CONCLUSIONS: Low TC is strongly associated with increased mortality in patients with HF. Further study is warranted to determine the nature of this relationship, optimal lipid levels, and the role of statins in patients with HF.