South Africa has increasing numbers of persons living with HIV on antiretroviral treatment (ART). There is evidence for a relationship between food, food security and HIV. Despite increasing rates of people older than 50 living with HIV coinciding with greater levels of co-morbidity, the existing research is largely limited to those aged 15–49 years. In this paper, we therefore explore how older people living with HIV (OPLWH) in two urban communities within South Africa negotiate and ensure they have sufficient access to food and how food insecurity may affect their retention in care and ART adherence. This study used exploratory qualitative semi-structured in-depth interviews with 23 OPLWH to collect data in isiXhosa. Data were analysed using thematic content analysis. Factors at the community, household and individual levels influence (a) access to sufficient and quality food, and (b) beliefs about ART and food based on (mis)understandings of messaging from health care providers. The results demonstrate the need to explore further and clarify the nutritional guidelines that OPLWH receive from providers to ensure this does not result in reduced adherence or retention in care. They also demonstrate the role that social welfare and family or kin obligations plays in ensuring the food security of OPLWH.