Abstract: The purpose of the current study was to conduct a comprehensive meta-analytic review of Cognitive Processing Therapy (CPT) for PTSD among military personnel and veterans. Additionally, we sought to examine potential moderators of treatment outcomes including type of comparison condition (e.g., active trauma-focused, active non-trauma-focused), CPT version (i.e., CPT with and without the written trauma account), sample type (veteran or military personnel), age, gender, and race. Nine articles with 1,804 participants were retained for this meta-analysis. CPT, when compared to all comparison conditions, exhibited a medium effect on PTSD symptom reduction (Hedge’s g = − 0.48, 95% CI: -1.05, 0.08). Regarding moderators, the effect was larger for non-trauma-focused active comparators versus trauma-focused active comparators (Qbetween = 16.69, pbetween < 0.001, Hedge’s g = − 0.57 and − 0.14, respectively). Further, CPT with the written trauma account outperformed CPT without the written trauma account (Qbetween = 4.53, pbetween = 0.03, Hedge’s g = − 0.86 and − 0.23, respectively), and veteran samples saw slightly more symptom reduction than military personnel (Qbetween = 15.50, pbetween < 0.001, Hedge’s g = − 0.51 and − 0.45, respectively). Notably, age, gender, and race did not moderate the effect of CPT on PTSD. Findings support the continued use of CPT for PTSD symptoms among veterans and military personnel and call into question the removal of the written trauma account.