Objective: Patterns of low autonomic arousal have consistently been related to delinquency and disruptive behavior disorders (DBD) in children and adolescents. Findings on another stress regulating mechanism, the hypothalamic pituitary adrenal (HPA) axis, have been inconsistent, which may partly be due to not considering specific stress reactivity measures. Therefore, the aim of the present study was to investigate the relationship between disruptive behavior in male adolescents and their HPA and autonomic reactivity to a standard public speaking task (PST). Method: Responsivity to the PST of cortisol, heart rate (HR), skin conductance level (SCL) and self-reported negative feelings was measured, and compared between 12and14-year-old boys who attended a delinquency diversion program (DP), with and without DBD (DP+, n=22 and DP-, n=49, resectively), and matched normal controls (NC, n=30). DBD diagnoses were based on a structured psychiatric interview. Results: The DP+ group, but not the DP- group, showed a significantly decreased cortisol and HR response during the PST as compared with the NC group. No significant effects were found for SCL. All subjects connoted the task negatively. Conclusions: The results indicate that low cortisol and HR responsivity to stress may be a neurobiological marker for delinquent boys with DBD, but not for those without DBD. Directions for future research and clinical implications are discussed.