Background: Women face significant threat from cardiovascular disease (CVD), and this threat increases with age. Physical activity (PA) has been shown to reduce the risk of CVD in women; furthermore, self-efficacy has been identified as a strong predictor of whether a woman will engage in this health behavior. Purpose: To explore the relationship between women’s risk for CVD and self-efficacy beliefs in relation to the behavior of physical activity. Methods: The Health Promotion Model was used to guide the retrospective, cross-sectional study. The sample (n=120) included participants from the Happy Hearts Health Promotion Program (HHHPP), an intervention study aimed at improving cardiovascular risk for CVD. Baseline data was analyzed using descriptive, bivariate, and multivariate analyses. Results: On average, the women in this sample were 68 years old, overweight, highly educated, and highly active. Bivariate analyses revealed no significant correlation between cardiac risk and self-efficacy, but a positive correlation was identified between BMI and frailty, and a general decline in walking activity (6MWT) with increasing age. In regression analysis, frailty emerged as a significant predictor of the total and subtypes of Multidimensional Self-Efficacy for Exercise (R²= 2.9%-11%). Moderate self-reported physical activity and the 6MWT were the only activity measures to significantly predict any of the self-efficacy variables. Discussion: Nurses are ideally positioned to lead health promotion initiatives, such as evidence based exercise self-efficacy enhancing interventions and educational strategies for aging women that focus on the importance of physical activity in reducing the risk of CVD and frailty. As a holistic approach is central to nursing, it is important for nurses to incorporate the components of self-efficacy, frailty, and CVD risk into their assessments and ongoing care of aging female patients. Significance: This study provides novel research evidence regarding the influence of frailty on the exercise self-efficacy of aging women at risk for heart disease; furthermore, the study findings support emerging data related to the relationship between BMI and frailty. This research establishes foundational evidence for future nursing research aimed at strengthening the exercise self-efficacy beliefs of aging women with the goal of improving physical activity to reduce CVD and frailty risk.