Data suggest military personnel involved in U.S. military initiatives in Iraq and Afghanistan are returning from deployment with elevated rates of mental health diagnoses, including posttraumatic stress disorder (PTSD). The aim of this study was to examine difficulties with emotion regulation as a potential contributory mechanism by which soldiers have poorer psychological outcomes, such as depression, dissociation, alcohol abuse, and interpersonal difficulties. Participants were 44 active-duty male service members who comprised three groups, including those deployed with and without diagnosed PTSD and those prior to deployment. Participants in the PTSD group scored significantly higher on measures of self-reported depression, trauma-related dissociation, alcohol misuse, and social adjustment difficulties than did comparison groups. Importantly, difficulties with emotion regulation were found to partially mediate the relationship between PTSD and depression, poor social adjustment, and trauma-related depersonalization but not alcohol misuse. Emotion-regulation difficulties are important to consider in the relationship between PTSD and additional psychological outcomes in recently deployed personnel. Implications for treatment are briefly discussed.