BACKGROUND: Adolescents living with HIV (ALHIV) are at high risk of experiencing mental health problems. Depression is a major contributor to the burden of HIV-related disease amongst ALHIV and is significantly linked to non-adherence to anti-retroviral therapy (ART), yet it is under-recognized. In 2015, the Baylor College of Medicine International Pediatric AIDS Initiative (BIPAI) recommended that the psychosocial screening tool Home, Education, Activities, Drugs, Sexuality, Suicide/Depression (HEADSS) be used to screen ALHIV in Malawi who were part of an adolescent antiretroviral therapy program termed "Teen Club". However, the HEADSS tool has been substantially under-utilized. This study assessed barriers and facilitators to implementing HEADSS for ALHIV attending Teen Club Program in four selected health facilities in Malawi. METHODS: We conducted a qualitative study using semi-structured interviews at four program sites (one district hospital and one health center each in two districts) between April and May 2019. Twenty key informants were purposively selected to join this study based on their role and experiences. We used the five domains of the Consolidated Framework for Implementation Research (CFIR) to guide the development of the interview guides, analysis and interpretation of results. RESULTS: Barriers included inadequate planning for integration of the HEADSS approach; concerns that the HEADSS tool was too long, time consuming, lacked appropriate cultural context, and increased workload; and reports by participants that they did not have knowledge and skills to screen ALHIV using this tool. Facilitators to implementing the screening were that health care providers viewed screening as a guide to better systematic counselling, believed that screening could build better client provider relationship, and thought that it could fit into the existing work practice since it is not complex. CONCLUSIONS: A culturally adapted screening tool, especially one that can be used by non-clinicians such as lay health workers, would improve the ability to address mental health needs of ALHIV in many primary care and social service settings where resources for professional mental health staff are limited. These findings are a springboard for efforts to culturally adapt the HEADSS screening tool for detection of mental and risky behaviors among ALHIV attending ART program in Malawi.