Introduction: In South Korea, approximately 40% of older adults are reported to have low health literacy. The purpose of this study was to evaluate the relationship between health literacy and patient participation among Korean older adults with heart failure. Method: This cross-sectional descriptive study involved 145 Korean patients at one prominent medical center in South Korea. The Korean Health Literacy Scale short form and the 13-item Perceived Involvement in Care Scale were administered between June and September, 2016. Results: Among participants (mean age = 71.30 years; 26.9% female), approximately 30% had poor health literacy. A significant correlation was observed between health literacy and participation scores (r = .538, p < .01). Health literacy was the most important predictor of patient participation (β = .488, p < .001). Discussion: The results imply that effective knowledge acquisition may encourage greater patient participation. By identifying health literacy in Korean older adults, we can provide more culturally congruent health care by improving participation between providers and patients.