Abstract Recent investigations propose that cognitive characteristics of autobiographical memory significantly interact with Posttraumatic Stress Disorder (PTSD). A traumatic event becoming more or less central in a person’s identity and life story might influence development of the disorder. Studies show high correlations between event centrality (EC) and PTSD. Participated in this study 68 treatment-seeking individuals referred to a specialized service for suspected trauma-related disorder: 39 matched criteria for PTSD and 29 were exposed to trauma without PTSD. Our aims were to explore how the groups differ regarding EC, depression, anxiety, posttraumatic cognitions, PTSD symptom severity, and peritraumatic dissociative experience; and how distinctively EC interacts with the measures in each group. The PTSD group had higher scores in all variables but dissociation. EC correlated with overall PTSD symptoms only in the PTSD group and with dissociation only in the no-PTSD group. Findings support a model emphasizing the role of memory processes in PTSD. People exposed to trauma who developed PTSD had the memory of the traumatic experience more intensively governing their sense of self and thus eliciting more negative cognitive reactions. As EC facilitates recollection of the traumatic event, it could also mediate a semantization process that reinforces and increases posttraumatic symptoms.