For the first time, the present study investigates disorder-specific attachment characteristics and childhood trauma in adolescent inpatients with anorexia nervosa (n = 30, girls/boys: 28/2, age: M = 14.84, SD = 1.20), a major depressive episode (n = 30, girls/boys: 27/3, age: M = 15.14, SD = 1.50), and controls (n = 60, girls/boys: 44/16, age: M = 16.10, SD = 1.20). We used the Structured Clinical Interview to diagnose Axis I disorders, the Adult Attachment Projective Picture System to classify attachment representations, and the Childhood Trauma Questionnaire to assess child maltreatment. Our findings demonstrate an overrepresentation of the unresolved attachment status in the patient samples. A one-way analysis of variance succeeded by Bonferroni post hoc tests indicated that adolescents with anorexia nervosa show more isolation and dissolution of boundaries between life and death when confronted with situations of solitude. Although they report moderate to severe levels of traumatic childhood experiences, they tend to minimize those. Adolescents with a major depressive episode report higher levels of emotional abuse and neglect in their childhood, leaving them in a state of failed protection and danger during attachment distress. Integrating these attachment-related characteristics into specific psychotherapeutic interventions might be associated with a better outcome in that age group.