The World Health Organization recommends disclosure of parental HIV to children aged 6-12 years. The maternal HIV-disclosure intervention (Amagugu), a lay counsellor-led, home-based intervention with six sessions, was implemented. The intervention included provision of disclosure tools, training and support for mothers, a family session and health promotion clinic visit for mothers and children. Amagugu demonstrated success as a maternal disclosure support programme but less is known about the experiences of participants. A sub-sample of HIV-infected mothers (n = 20) with primary school-aged HIV-uninfected children, from Amagugu, was purposely selected. Using semi-structured interviews and interview-guide, we explored maternal perceptions of disclosure prior to participation and experiences of participating in Amagugu. Audio-recorded interviews conducted in participants' homes, in isiZulu, were transcribed, and content analysis was undertaken. The most common reasons for prior non-disclosure were concerns about children's developmental capacity to understand HIV, fear of HIV-related stigma towards mothers and their families, and lack of skills to undertake disclosure. Intervention materials, rapport with counsellors, and flexibility of the proposed disclosure process motivated mothers to participate. While expressing satisfaction with the intervention, some mothers remained concerned about their children's understanding of HIV and ability to maintain confidentiality. Mothers also requested support in discussing sex-related topics with their children. Despite prior high rates of disclosure to other adults, mothers had little awareness about the importance of disclosure to children and lacked skills to undertake this. The intervention approach, rapport with counsellors, and practicality of the materials, helped overcome child disclosure barriers. Mothers reported their children as very supportive following disclosure and stated they would advise other women to disclose to children for practical support around HIV treatment adherence. This qualitative evaluation suggests that mothers with primary school-aged children may require structured support when disclosing to children, which could be achieved through supportive home-based counselling and user-friendly materials.