In this study we tested for a protective effect of secure attachment representations in the development of posttraumatic stress disorder (PTSD). In a design with a control group, we replicated and extended a recent study that found no underrepresentation of secure attachment representations in veterans with PTSD (Nye, Katzman, Bell, Kilpatrick, Brainard, & Haaland, 2008). Furthermore, we examined the association of the Adult Attachment Interview (AAI) classification of unresolved loss or trauma and PTSD symptomatology. The Adult Attachment Interview and the Clinician Administered PTSD Scale (CAPS) were administered with 31 veterans with PTSD and 29 trauma-exposed veterans without PTSD of similar age and country of deployment. Patient and control groups did not differ in the prevalence of secure attachment representations, neither did unresolved and not unresolved subjects differ in prevalence of secure attachment representations. Unresolved state of mind with respect to deployment related trauma was found to correlate strongly with total CAPS score. This study shows no protective effect of secure attachment representations in the development of PTSD. AAI unresolved state of mind with respect to deployment related trauma and PTSD correlate strongly, due to the common core phenomenon of lack of integration.