['Social support may be associated with heart failure (HF) self-care; however, the mechanisms are not well understood. We examined the association between perceived support and self-care behaviors and whether self-care confidence mediates these relationships.', 'Cross-sectional survey of HF patients seen in outpatient clinic settings. Our outcome (HF self-care maintenance and self-care management) and mediator (HF self-care confidence) variables were assessed with the Self-Care of Heart Failure Index. Perceived emotional/informational support was assessed with the Medical Outcomes Study social support survey. We performed regression analyses to examine associations between perceived support and HF self-care behaviors. Mediation analysis was performed according to the Baron and Kenny method.', 'We surveyed 150 HF patients (mean age 61 y; 51% female; 43% black). More emotional/informational support was associated with better self-care maintenance (β = 0.13; P = .04). More emotional/information support was associated with better self-care management in unadjusted (β = 0.23; P = .04), but not adjusted (β = 0.20, P = .10), analysis. Self-care confidence mediates the association between perceived support and self-care maintenance (percent change in β coefficient was 32%) and management (percent change in β coefficient was 20%).'] Does self-care confidence mediate the relationship between perceived social support and self-care maintenance in adults with heart failure?