Objective: To determine subsequent risk of unintentional injury among preschool boys diagnosed with ODD, boys with comorbid ODD and ADHD, and boys matched demographically to the clinical sample; to test predictive validity of a measure of injury proneness; and to examine factors that might predict injury beyond clinic status. Methods: Seventy-nine consecutive clinic-referred preschool-age boys and 76 demographically matched boys without disruptive behavior participated in a 2-year prospective longitudinal design. Time 1 assessment included clinical diagnosis, parent-reported injury proneness, attachment, and verbal abilities. Injury history was measured 1 and 2 years later. Results: Clinic-referred children had more injuries than the comparison group. Children with comorbid ODD and ADHD had approximately the same injury rate as those with ODD but not ADHD. Parent-reported injury proneness was unrelated to subsequent injuries. Neither attachment nor verbal ability predicted injury significantly beyond clinic status. Conclusions: Children with early disruptive behavior are at increased risk of unintentional injury and therefore should be considered prime candidates for injury prevention campaigns.