This study examined how personality disorders (PD) differ with respect to gender, attachment status and traumatic childhood experiences in adolescent psychiatric inpatients. In particular, we investigated attachment-related traumatic material underlying adolescent PD. Our sample consisted of 175 inpatient adolescents aged 14 to 18 years (77% female, Mage = 15.13, SD = 1.35; 23% male, Mage =14.85, SD = 1.41). Thirty-nine patients (22%) fulfilled the diagnostic criteria for a PD according to the SCID-II PD: 51% avoidant, 13% obsessive-compulsive, 13% antisocial, 19% borderline, 2% paranoid and 2% histrionic. In the total sample, eighty-three (47%) of our inpatients were classified with an unresolved attachment status using the Adult Attachment Projective Picture System (AAP). We did not find any significant gender differences for patients with and without a PD. Our results revealed a higher percentage of unresolved attachment status in patients with a PD. The in-depth analysis of the total sample showed that patients with a PD demonstrated more traumatic material in their attachment interviews indicating a greater severity of attachment trauma. Furthermore, patients with a PD reported higher scores on emotional and physical neglect. Intervention strategies targeting traumatic attachment-related themes might be useful to treat adolescents with PD.