Recent research has provided evidence for a dissociative subtype of posttraumatic stress disorder (PTSD). However, previous research has primarily utilized samples of adults exposed to acute traumatic stressors. Therefore, further research is needed to investigate the dissociative subtype in samples of youth and those exposed to more chronic forms of trauma. Further, studies have not yet tested empirically- and theoretically-derived constructs that are purported to increase the likelihood of subtype membership. This study investigated whether peritraumatic dissociation, emotion dysregulation, gender, and betrayal trauma exposure affected the likelihood of dissociative subtype membership in trauma-exposed detained youth. Results indicated that half of the sample met subtype criteria and peritraumatic dissociation and emotion dysregulation were associated with subtype membership. Results suggest that dissociative subtype membership may be more common in youth, particularly among those youth involved in the justice system, and highlights the clinical utility of screening for dissociative symptoms in young persons.