Objective To measure the peak oxygen consumption (peak VO2) and oxygen uptake at anaerobic threshold (VO2AT) by cardiopulmonary exercise testing (CPET) in patients with chronic heart failure (CHF) and evaluate the prognostic values of the 2 indices. Methods Totally 129 patients suffering from CHF with left ventricular ejection fraction (LVEF)＜0.49 by echocardiography admitted in our department were recruited in this study. Coronary angiography indicated that there were 74 cases of ischemic cardiomyopathy and 55 cases of dilated cardiomyopathy. All subjects underwent CPET on the bicycle ergometer and were followed up for cardiac-related mortality in duration of median 33.7 months. Results (1) During the follow-up, 19 cardiac deaths were identified. There was no differences in the age, sex, body mass index (BMI) and peak respiratory exchange ratio (peak RER) between those dead patients and the survivors (P＞0.05). But LVEF (0.33±0.09 vs 0.38±0.09), peak VO2 [11.8±4.3 vs 14.4±3.7ml/(kg·min)] and VO2AT [9.3±3.2 vs 10.7±2.1ml/(kg·min)] were obviousty lower, while left ventricular mass index (LVMI, 158.3±53.9 vs 133.2±40.1) was significantly higher in the dead ones than in the survivors (all P＜0.05). (2) By receiver operating characteristic (ROC) curve analysis, the area under curve (AUC) of peak VO2 was 0.640 in predicting cardiac-related mortality in CHF patients (P＜0.05), the sensitivity was 0.590, the specificity was 0.667, and the optimal threshold value of peak VO2 was ≤13.4ml/(kg·min). The AUC of VO2AT was 0.600 (P＜0.05), the sensitivity was 0.886, the specificity was 0.360, and the optimal threshold value of VO2AT was ≤8.2ml/(kg·min). Conclusion Peak VO2 and VO2AT have certain predictive values for cardiac-related mortality in CHF patients, and the former is superior to the latter.