Cardiometabolic disorders (CMD) such as hypertension and diabetes are increasingly prevalent in sub-Saharan Africa, placing people living with HIV at risk for cardiovascular disease and threatening the success of HIV care. Spouses are often the primary caregivers for people living with CMD, and understanding patients' and partners' conceptions of CMD could inform care. We conducted semi-structured interviews with 25 couples having a partner living with HIV and either hypertension or diabetes. Couples were recruited from HIV clinics in Malawi and were interviewed on beliefs around symptoms, causation, prevention, and treatment for CMD. Data were analyzed at the individual and dyadic levels using framework analysis and Kleinman's theory of explanatory models as a lens. On average, participants were 51 years old and married for 21 years. Approximately 57%, 14%, and 80% had hypertension, diabetes, and HIV. Couples endorsed a combination of biomedical explanatory models (beliefs around physical and mental health) and traditional explanatory models (beliefs around religion and natural remedies), although tended to emphasize the biomedical model. Half of couples believed stress was the main cause of hypertension. For diabetes, diet was believed to be a common cause. In terms of prevention, dietary changes and physical activity were most frequently mentioned. For disease management, medication adherence and diet modifications were emphasized, with some couples also supporting herbal remedies, stress reduction, and faith in God as strategies. Participants were generally more concerned about CMD than HIV due to poor access to CMD medications and beliefs that CMD could lead to sudden death. Within couples, partners often held many of the same beliefs but diverged around which etiological or preventive factors were most important (e.g., stress versus diet) and the best diet for CMD. Health education programs should involve primary partners to build knowledge of CMD and address overlap with HIV, and reinforce accurate information on lifestyle factors for the prevention and treatment of CMD.