Background. Caregivers are crucial in ensuring that their relatives with heart failure (HF) reach proper self-care levels. Despite this, the demanding nature of caring for others can lead to poor outcomes and the compromise of own needs, which raises the need for perceived social support. Prior research does not offer a thorough knowledge of how caregivers of people with HF regarded social support and the characteristics that went along with it. Purpose. The aim of this study was to develop a comprehensive understanding of perceived social support and its associated factors among caregivers of individuals with heart failure. Methods. This is a secondary analysis of a convergent mixed-methods design study. The perception of social support, mutuality, anxiety, depression, and quality of life were assessed in 158 heart failure patients and their caregivers (physical and mental dimensions). In 50 caregivers, we also performed semistructured interviews. Results. The mixed analysis and integration of qualitative and quantitative inferences revealed two main factors affecting perceived social support. First, caregivers with strong familial network and greater number of caregivers available for tangible caregiving support and moral support perceived increased sense of social support. Second, caregivers with enhanced mental health had increased sense of social support. Conclusions. Caregiver perception of social support might be influenced by mental well-being status. To improve caregivers’ perceptions of social support and community belonging, it is necessary to create and assess community- and individual-based mental health promotion interventions. To strengthen the perception of support in the heart failure caring process, more dyadic strategies should be established to improve patient-caregiver mutuality.