There is limited evidence on the degree of cognitive impairment and its association with physical functional capacity among patients with heart failure (HF) in Korea.In this study, we compared cognitive impairment between patients with HF and community-dwelling participants with non-HF medical conditions (medical participants) and its association with physical functional capacity.We conducted a cross-sectional comparative study and assessed the neuropsychological cognitive status (Seoul Neuropsychological Screening Battery) and physical functional capacity (Duke Activity Status Index) of patients with HF and medical participants using face-to-face interviews.One hundred and eighteen patients with HF (age, 65.45 ± 9.38 years; men, 57.6%; left ventricular ejection fraction, 34.93 ± 8.72%) and 83 medical participants (age, 66.02 ± 8.28 years; men, 47.0%) were included. Using seventh-percentile medical participant Z-scores as cutoffs, memory and executive function were worse in patients with HF than in medical participants: immediate (35.0% vs. 6.0%) and delayed recall memory (34.5% vs. 8.4%), and executive function (28.6% vs. 6.0%). Independent of age, sex, education, comorbidity, and HF status, executive function was a significant predictor of physical functional capacity (b = 1.82, p = .021).More patients with HF had impaired memory and executive function, which were associated with their physical functional capacities.