This report examines the relationship between treatment response in children with ASD and parents' affective symptomatology. This study examined 29 children with ASD in a manualized group psychotherapy program, Resilience Builder Program® (RBP), where emotional and social functioning of parent and child were measured through pre- and post-treatment questionnaires. Greater parental symptomatology was associated with children's reduced response to RBP in resilience-based emotion regulation skills. Greater parental interpersonal sensitivity ([beta] = - 0.27, p = 0.024) predicted worse post-treatment scores in child communication skills, greater parental anxious symptoms ([beta] = - 0.45, p = 0.005) predicted worse post-treatment scores in child emotional control, and greater parental depressive ([beta] = 0.27, p = 0.041) and anxious symptoms ([beta] = 0.36, p = 0.004) predicted worse post-treatment scores in child internalizing problems.