BACKGROUND: Of the estimated 130,000 children living with HIV in Uganda, 47% are receiving ART. Only 39.3% have suppressed HIV-1 viral load to levels below 50 copies per ml. Caregivers are key drivers of adherence to achieve viral suppression in children. We investigated the challenges and potential support required by caregivers of ART-treated children. METHODS: A qualitative study was conducted within the Infectious Diseases Institute paediatric ART program in Kampala and Hoima districts. Caregivers of children with viral loads above 1000 copies were purposively sampled and engaged in five focus group discussions (FGD). The FGD guide highlighted questions on challenges that caregivers face and the kind of support they required to improve children's ART adherence. Thematic analysis using the inductive approach was used. All the transcripts were read, coded and emergent themes determined. RESULTS: Overall, 37 caregivers participated in five FGD, of whom 29 (78%) were female, 28 (76%) were HIV-infected and 25 (68%) were biological parents of the children. The elicited challenges were either in failure to attend the counselling sessions or in supporting adherence to medication. Individual and health system challenges such as competing priorities, logistics, poor quality of counselling and lack of reminders prevented attendance at counselling sessions. Five themes emerged as challenges to supporting adherence: i) environmental (school activities, working away from home), ii) personal (non-disclosure, stigma), iii) psychological (guilt), iv) financial (lack of food and transport) and v) child-related (fatigue and peer influence). Three major themes emerged for the support that caregivers needed namely: a) health system reforms (clinic appointments outside school hours, minimize ART drug stock outs and improve quality of counselling), b) psychosocial support (support with disclosure of HIV status to children and their families, more frequent peer support groups and parenting classes) and c) economic empowerment (training in vocational skills, school fees support and opportunities to initiate income generating activities). DISCUSSION AND CONCLUSION: To achieve viral suppression, ART programs require targeted efforts to provide specific health facility requirements, psychological and economic needs of ART-treated children and their caregivers. Integration of HIV treatment with programs for orphans and vulnerable children may improve viral suppression rates.