Abstract: Objective: To explore the relationship between positive parenting style and junior middle school stu-dents’oppositional defiant disorder (ODD) and the potential mediating role of school bullying and mental subhealth in this relationship, so as to reduce the risk of junior middle school students’oppositional defiant disorder.Methods: A total of 881 first-year students from two middle schools in Wuhan were selected using cluster sam-pling in November 2019.The Destructive Behavior Disorder Rating Scale, Egma Minnen av Bardndosnauppfor-stran, Chinese version of Olweus Bully/Victim Questionnaire and Multidimensional Sub-health Questionnaire of Adolescents were used to measure ODD, positive parenting style, school bullying and mental sub-health of ado-lescents.A chain mediating model was used to analyze the mediating role of school bullying and mental subhealth in the relationship between positive parenting style and ODD.Results: Of the 839 junior middle school students (53.99% for males and 46.01% for females), positive parenting style was negatively associated with school bullying, mental sub-health and oppositional defiance disorder (P< 0.01).School bullying, mental subhealth and ODD were significantly positively correlat-ed (P< 0.05).Positive parenting style could signifi-cantly predict ODD through the two mediating paths of mental sub-health and school bullying and mental sub-health (with effect sizes of-0.096 and-0.006, re-spectively).Conclusion: Positive parenting style can indirectly affect ODD through mental sub-health and school bullying-mental sub-health.