Objective: Because aggressive behavior is observed in more than half of children and adolescents with attention deficit hyperactivity disorder (ADHD), it is essential to identify relating factors that explain this association in individuals who are susceptible to childhood trauma. This study aims to investigate the relationship between aggression and psychoform and somatoform dissociative experiences, while controlling for the effect of childhood trauma in young adults at risk for ADHD. Materials and Methods: Participants were 137 university students who voluntarily completed a series of measurements, including a socio-demographic form, the Adult ADHD Severity Rating Scale (ASRS), the Childhood Trauma Questionnaire (CTQ), the Dissociative Experiences Scale (DES), the Somatoform Dissociation Questionnaire (SDQ), and the Buss–Perry Aggression Questionnaire (AQ). Based on ASRS scores, participants were divided into two groups: low and high risk for ADHD. Results: CTQ (d = 0.54; P <.01), DES (d = 0.85; P <.01), SDQ (d = 0.78; P <.01), and AQ (d = 0.72; P <.01) scores were significantly higher in the high-risk ADHD group than in the low-risk group. Linear regression analyses revealed that in the high-risk group, hyperactivity/impulsivity (t = 2,75; P =.02), body mass index (t = 2,85; P <.01), and somatoform dissociation (t = 3,20; P <.01) were statistically significant predictors of aggression. Conclusion: When evaluating the trauma/dissociation process in individuals with ADHD, somatoform dissociation may be a significant predictor of aggression. Longitudinal studies in the clinical ADHD population are needed to confirm and clarify this relationship.