Psychological trauma and post-traumatic stress disorder (PTSD) are under-researched in autistic individuals. We explored the experience of trauma and PTSD symptoms in a sample of autistic adolescents (n = 30) aged 10-16 years (without a maltreatment history; 47% female), compared to a group of typically-developing (TD; n = 29) and a group of (non-autistic) maltreatment-exposed adolescents (n = 28), matched on key demographics. Caregiver reports indicated that a wide range of events were deemed traumatic to autistic adolescents, including those not meeting DSM-5's Criterion A for trauma for a PTSD diagnosis (e.g., bullying and bereavement). Caregiver- and self-reports converged to show more severe PTSD symptoms, and higher rates of probable PTSD, in autistic adolescents (43-57%) relative to the TD adolescents (7-32%). Symptom severity and rates of probable PTSD were comparable between the autistic and maltreatment-exposed adolescents (50-54%), except that, for autistic adolescents, the index trauma mostly did not match DSM-5 criteria, whereas it did for maltreatment-exposed adolescents. This short report's early findings supports the need for improved assessment of trauma exposure and PTSD symptoms in autistic adolescents. A flexible approach to how trauma is defined in this population may be needed, considering subjective experiences and autism-related processing differences.