ABSTRACTObjectives: LGBTQ+ based discrimination is a form of insidious trauma and minority stress, and is associated with poor mental health. However, there is a dearth of research on the impact of discrimination on the psychological functioning of LGBTQ+ individuals who have experienced trauma. The current study seeks to remedy this gap. It was hypothesized that: (1) LGBTQ+ adults who perceived their experience of trauma as related to LGBTQ+ based discrimination would have greater attachment insecurity, emotion dysregulation, PTSD symptoms, and dissociative symptoms; (2) experiences of LGBTQ+ based discrimination would be associated with greater attachment insecurity, emotion dysregulation, PTSD symptoms, and dissociative symptoms; (3) transgender congruence (i.e., the extent to which one feels authentic and comfortable with their gender identity and appearance) would be negatively associated with attachment insecurity, emotion dysregulation, PTSD symptoms, and dissociative symptoms. Methods: Participants were 157 LGBTQ+ adults who had experienced trauma, and who completed questionnaires on discrimination and psychological functioning. Results: Compared to participants who did not experience their trauma as related to discrimination, those who did were higher in attachment anxiety, attachment avoidance, emotion dysregulation, PTSD, and dissociative symptoms. Biphobia was positively associated with attachment anxiety, emotion dysregulation, PTSD, and dissociative symptoms. Homophobia was positively associated with emotion dysregulation, PTSD, and dissociative symptoms. Transphobia was positively associated with PTSD and dissociative symptoms. Appearance congruence was negatively associated with emotion dysregulation, PTSD, and dissociative symptoms. Conclusions: When working with LGBTQ+ clients who have experienced trauma, clinicians should be mindful of the effects of discrimination on wellbeing.