Lesbian, gay, bisexual, trans, and queer individuals (LGBTQ+) report higher rates of suicide-related behaviors when compared to heterosexual cisgender individuals. The minority stress theory proposes that the suicide risk disparities among LGBTQ+ individuals may be explained by the additional exposure to stressors unique to their minority sexual orientation and gender identity. However, less is known about the mechanism of minority stressors and suicide risk among trauma-exposed LGBTQ+ individuals. The present study aimed to explore the role of the International Classification of Diseases, version-11 posttraumatic stress disorder (PTSD) and complex PTSD (disturbances in self-organization [DSO] + PTSD) in the associations between minority stressors and suicide intent in a sample of 229 trauma-exposed LGBTQ+ adults from Spain. Mediation analyses were conducted in Mplus 8.4 to test the impact of PTSD and DSO on the association between minority stressors and the self-reported likelihood of suicide intent. Results indicated that the cumulative daily cisheterosexist experiences had an impact on the likelihood of suicide intent through DSO. Specifically, gender expression-related harassment, and isolation due to sexual/gender identity increased the DSO symptoms, which, in turn, increased the likelihood of suicide behavior. Exploring minority stressors and targeting the components related to DSO, such as negative self-concept, affective dysregulation, and disturbances in relationships, may help clinicians in improving interventions aimed at reducing suicide-related behaviors in LGBTQ+ adults.