Abstract: This study investigated the role of core self-evaluations (CSE) as a mediating factor between posttraumatic stress disorder (PTSD) symptoms and well-being among Veterans and examined gender as a moderator of the indirect effect of PTSD on well-being through CSE. Participants comprised 205 Veterans (Mage = 29.3, SD = 8.0). We evaluated a simple mediation model to assess the potential influence of PTSD symptoms on well-being and the role of CSE as a mediator in this relation. Furthermore, we introduced gender as a moderator variable into the model and tested for moderated mediation. Our study demonstrates that CSE mediates the relationship between PTSD symptoms and well-being, and gender moderates the relationship between PTSD symptoms and well-being through CSE in a sample of Veterans. Our findings suggest that female Veterans are more prone to lower CSE. Addressing gender differences may be imperative to support Veterans. Limitations and clinical implications are discussed.