The oxygen uptake efficiency slope (OUES) response has not been characterized in heart failure (HF) patients with a normal ejection fraction (NEF). Fifty-nine subjects with systolic HF, 59 with HF-NEF and 28 healthy age-matched controls participated in this analysis. The OUES (systolic HF: 1.23 ±0.41 vs. HF-NEF: 1.22 ±0.30 vs. controls: 1.51 ±0.49) was significantly reduced in both HF groups compared to controls (p<0.001). Compared to healthy controls, the OUES is reduced in HF-NEF patients to a similar degree as those with systolic HF. Thus, as in systolic HF, the OUES may provide clinically useful information in patients with HF-NEF.