Purpose <p>Parents of children with autism spectrum disorder (ASD) face elevated risks of depressive symptoms, which may impair their daily functioning and hinder effective caregiving. Grounded in self-determination theory and conservation of resources theory, this study examined the bidirectional relationship between basic psychological needs (autonomy, competence, relatedness) satisfaction and depressive symptoms, as well as the potential mediating effect of parenting stress in this relationship.</p> Methods <p>Using a two-wave cross-lagged design, we assessed 178 Chinese parents of autistic children at baseline and at the three-month follow-up. The participants completed questionnaires on basic psychological needs satisfaction, depressive symptoms, and parenting stress at two waves of survey.</p> Results <p>The results supported the reciprocal relationship between autonomy need satisfaction and depressive symptoms, as well as the predictive effect of depressive symptoms on subsequent competence/relatedness need satisfaction. The findings also established parenting stress as a bidirectional mediator: it not only mediated the negative effects of depressive symptoms on the three psychological needs satisfaction, but also served as a mechanism through which autonomy need satisfaction buffers against mental health decline.</p> Conclusion <p>These findings highlight the necessity of developing interventions that enhance autonomy support and mitigate parental stress to improve the well-being of parents of autistic children.</p>