This study examined whether, and to which extent, the associations between conflict intensity and children’s and early adolescents’ functioning problems were mediated through parental harsh discipline in a post-armed conflict setting. Data from 9623 Iraqi mothers and their children who participated in UNICEF MICS showed that the associations between conflict intensity, parental discipline and child functioning were similar for children and early adolescents. Higher conflict intensity was indirectly associated with increased anxiety and depression, greater learning and cognitive difficulties, and greater social and behavioural problems through parental harsh discipline. The proportion mediated effect sizes emphasised the importance of parent-focused interventions in improving child and adolescent functioning outcomes in conflict-affected populations.