ABSTRACT Background: Childhood maltreatment is a risk factor for developing multiple forms of psychopathology, including depression, posttraumatic stress disorder (PTSD), and anxiety. Yet, the mechanisms linking childhood maltreatment and these psychopathologies remain less clear. Objective: Here we examined whether self-stigma, the internalization of negative stereotypes about one's experiences, mediates the relationship between childhood maltreatment and symptom severity of depression, PTSD, and anxiety. Methods: Childhood trauma survivors (N = 685, Mage = 36.8) were assessed for childhood maltreatment, self-stigma, and symptoms of depression, PTSD, and anxiety. We used mediation analyses with childhood maltreatment as the independent variable. We then repeated these mediation models separately for childhood abuse and neglect, as well as the different subtypes of childhood maltreatment. Results: Self-stigma significantly mediated the relationship between childhood maltreatment and depression, PTSD, and anxiety symptoms. For sexual abuse – but not physical or emotional abuse – a significant mediation effect of self-stigma emerged on all symptom types. For childhood neglect, self-stigma significantly mediated the relationship between both emotional and physical neglect and all symptom types. Conclusion: Our cross-sectional study suggests that different types of childhood maltreatment experiences may relate to distinct mental health problems, potentially linked to increased self-stigma. Self-stigma may serve as an important treatment target for survivors of childhood abuse and neglect.