Exercise intolerance is a clinical feature of chronic heart failure (CHF) that reflects impaired cardiovascular performance. Increased arterial stiffness is associated with adverse outcomes in CHF. The cardio-ankle vascular index (CAVI) provides a reproducible, and noninvasive measure of arterial stiffness. This study aims to examine the relationship between CAVI and exercise intolerance among patients with CHF, providing new insights into the vascular contributions to functional limitation. This was a cross-sectional study involving adult patients with CHF. Subjects underwent CAVI assessment and the 6-minute walk test (6MWT) to evaluate exercise capacity. A 6MWT distance < 300 m was defined as exercise intolerance. Predictor variables for exercise intolerance were compared and analyzed statistically. Statistical analyses included bivariate group comparisons of CAVI value by exercise intolerance status, and a simple (univariable) logistic regression to assess their association (odds ratio [OR] and 95% confidence interval [CI]). Among 64 subjects, 36 (56.2%) demonstrated exercise intolerance. Subjects with exercise intolerance exhibited significantly higher CAVI values compared with those who maintained exercise tolerance. In simple logistic regression analysis, higher CAVI was associated with exercise intolerance (OR: 1.66; 95% CI: 1.10–2.71). Other bivariate predictor variables were body mass index > 25 (OR: 0.27; 95% CI: 0.08–0.80) and diabetes mellitus (OR: 4.10; 95% CI: 1.40–13.35). Increased arterial stiffness, as indicated by a higher CAVI, associated with exercise intolerance among CHF patients.