This article evaluates an Internet-based early intervention combining online cognitive-behavioral therapy (CBT) with electronic peer-to-peer support intended to promote mental health and well-being among combat veterans. We conducted a phase 1 clinical trial of 50 Iraq and Afghanistan veterans using a pre and post single-arm design. We evaluated feasibility and changes in mental health symptoms (depression and posttraumatic stress disorder [PTSD]), functional status, and attitudes toward treatment seeking at baseline and weeks 4, 8, and 12. A diverse group of veterans was enrolled (26% ethnic minority, 90% male, 66% with income <$30,000/year, 88% with no prior treatment for depression). Participants completed a mean of 4 of 6 lessons (standard deviation = 2.54). From baseline to week 12, there were significant declines in the Center for Epidemiologic Studies-Depression scale score (effect size [ES] = 0.41) and PTSD Checklist-Military version score (ES = 0.53). There were significant improvements in willingness to accept diagnosis (ES = 1.08) and perceived social norms and stigma regarding friends (ES = 1.51). Although lack of a control group is a limitation, the Internet-based program combining CBT-based coping skills training and peer-to-peer support demonstrated potential feasibility and evidenced benefit in symptom remediation for depression and PTSD.