Parents of children with autism spectrum disorder (ASD) experience stress, potentially affecting parenting and child outcomes. The roles of psychological flexibility and parental reflective functioning in coping strategies of parents of children with ASD are not fully understood. The study aims to examine differences in psychological flexibility, parental reflective functioning, parental self-efficacy, and coping strategies among parents of children with ASD and children with typical development (TD), while considering gender differences. In addition, it seeks to explore whether parental efficacy mediates the association between psychological flexibility, parental reflective functioning, and coping. The sample was comprised of 210 Israeli parents, with 86 having children with ASD and 124 having children with TD. A moderation analysis was conducted to investigate the moderation model. Parents of children with ASD demonstrated lower psychological flexibility, parental self-efficacy, and support-seeking coping strategies and higher proactive and disengagement coping strategies. Mothers reported higher parental reflective functioning and proactive and support-seeking coping strategies than fathers. In parents of children with ASD, parental self-efficacy mediated the association between parental reflective functioning and proactive coping strategies. Policymakers should advance intervention to enhance parental reflective functioning and parental self-efficacy for parents of children with ASD, with a special focus on fathers.