Confirmatory factor analyses (CFA) of posttraumatic stress disorder (PTSD) provided strong empirical rationale for changes to the PTSD criteria for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Recent statistical critiques suggested the CFA constraint to 0 cross-loadings has biased the findings of PTSD CFAs, leading to complex structural models that lack a priori theoretical justification and yield highly correlated factors. The aim of this study was to evaluate the DSM-5 PTSD factor structure using exploratory structural equation modeling (ESEM), which permits cross-loadings. Participants were trauma-exposed undergraduates (N = 1,139) who completed the PTSD Checklist for DSM-5. We evaluated 4-, 6-, and 7-factor models of PTSD in ESEM and CFA and found the 7-factor hybrid model to be best fitting. Comparisons between ESEM and CFA in the 7-factor model indicated presence of significant cross-loadings, justifying the use of ESEM. Compared to the 7-factor CFA, the 7-factor ESEM model was superior in fit, had lower factor loadings and factor intercorrelations, and exhibited better-differentiated patterns of associations with external correlates. These findings suggest that ESEM may be more appropriate than CFA for future investigations of PTSD factor structure.