Objective To explore the facilitators and barriers of family functioning among older adults living with HIV, so as to provide evidence for developing targeted family support and psychosocial intervention programs. Methods A descriptive qualitative study was adopted.Purposive sampling was used to recruit 17 pairs of HIV infected older adults receiving antiretroviral treatment and their primary caregivers.Based on the McMaster Model of Family Functioning, a semi-structured interview outline was compiled to conduct in-depth semi-structured interviews.Inductive content analysis was applied to collate and analyze the interview data. Results Facilitators of family functioning included positive mentality, improved disease cognition, and family role division and responsibility sharing.Barriers consisted of AIDS-related stigma, disease-related burdens, and a lack of family communication. Conclusion Family functioning among older adults living with HIV is affected by multiple factors.In the future, targeted interventions should be implemented to alleviate the barriers and activate the facilitators, and family-centered comprehensive interventions should be conducted to improve their family functioning and quality of life.