BACKGROUND: Adolescents with HIV are faced with challenges when taking care of their medication, which affects their treatment adherence. Therefore, this study aimed to explore the experiences and needs of adolescents living with HIV regarding their antiretroviral therapy adherence and retention in care in southern Ethiopia. METHODS: An inductive qualitative study design was applied to explore adolescents' experiences and needs regarding antiretroviral treatment adherence and retention in care in southern Ethiopia. Eighteen adolescents were selected from five HIV care and treatment facilities by purposive sampling. The interviews followed an interview guide, translated into the participants' national language. The interviews were transcribed verbatim and the first author developed a coding frame for the analysis by using NVivo software including meaning units and codes, which were discussed by all authors. Then, sub-themes and themes were identified and analyzed by qualitative content analysis. RESULTS: The results were described in two themes: barriers and facilitators for treatment adherence and retention in care. Barriers were described in seven subthemes and facilitators in three subthemes. Forgetting to take medication, hiding information, or non-disclosure of HIV status, being afraid to collect treatment drugs, being in an orphanage, and school activities were described as barriers while support from health care workers, families, personal motivation to cope with medication-related problems were described as facilitators for antiretroviral therapy adherence and retention in care. CONCLUSION: Adherence is a major challenge among adolescents living with HIV in Ethiopia, with barriers that are unique to this age group and their living conditions. Therefore, interventions should be targeted to address privacy barriers, stigma, and lack of support.