Background Child marriage remains a major child protection concern in Malawi and may increase during emergencies, particularly climate-related disasters. However, limited research has examined prevention efforts from the perspectives of stakeholders involved in intervention work. Objective This study explored how stakeholders understand the factors shaping child marriage, the barriers to prevention in emergency settings, and the interventions and coordination mechanisms used in Malawi. Methods A qualitative case study design was adopted. The purposive sample consisted of 20 NGO workers, government officials, and other stakeholders involved in child marriage prevention. Data were collected through qualitative interviews and analysed using reflexive thematic analysis. Results Four interrelated themes emerged. Economic hardship, cultural expectations, and gender norms were described as key drivers of child marriage, while prevention was viewed as a shared responsibility. In emergency settings, legal gaps and weak case reporting and follow-up reduced the effectiveness of prevention efforts. Participants also emphasized the importance of multi-level interventions and coordinated action among stakeholders. Conclusions Preventing child marriage in Malawi requires sustained and coordinated action that addresses poverty, gender norms, cultural influences, weak enforcement, and the disruption caused by emergencies. Stronger district-level protection systems, consistent case follow-up, and community-based interventions are needed before, during, and after disasters.