INTRODUCTION: Panama's HIV epidemic is far from under control. One of the populations with the fastest-growing epidemic among the Indigenous peoples of the Comarca Ngäbe-Buglé (CNB). The CNB is an administratively autonomous Indigenous region in Western Panama that is home to over 200,000 individuals of Ngäbe and Buglé ethnicities. This population is unique and, in several ways, represents the early stages of the AIDS epidemics in high-income countries. The CNB is the most impoverished region in Panama and is relatively isolated from outside influences, with limited roads, electricity, and an internet connection, including medical assistance. Around 1.5% of all rapid HIV tests are positive, compared to a national prevalence of 0.9%; in CNB, diagnosis tends to be late. In CNB, 56.3% of individuals had an initial CD4 count of <350 cells/mm3. Antiretroviral treatment (ART) dropout in this region is five times higher than the national average; there is high early mortality due to opportunistic infections. Using the Social-Ecological Theory for Health as a framework, this study aims to describe the facilitators and barriers associated with ART adherence and retention in HIV care among people living with HIV (PLHIV) in the CNB. A better understanding of factors that obstruct adherence could lead to more effective HIV care and prevention in CNB. METHODS: We conducted 21 semi-structured interviews with PLHIV who reside across all three regions of the CNB and have attended an antiretroviral (ART) clinic at least once. Deductive thematic analysis was used to uncover themes related ART adherence and retention in HIV care at the individual, social and structural levels. DISCUSSION: This unique, isolated population of rural Indigenous peoples has high infection rates, late diagnosis, poor ART adherence, and high AIDS-related death rates. The CNB is an important region to examen ART adherence and retention in care. We determined that psychological health, social support, and discrimination acted as individual-level facilitators and barriers to adherence and retention. Notably, structural barriers included difficult access to ART care due to travel costs, ART shortages, and uncooperative Western/Traditional medical systems. Recommended interventions used in other Low- and Middle-Income settings include increasing peer and family-level support and community knowledge and understanding of HIV infection. Additionally, our study suggests structural interventions, including decreasing the cost and distance of traveling to the ART clinic, by decentralizing services, decreasing food scarcity, and increasing collaboration between Western and Traditional providers.