Seventy-two veterans with traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), or both participated in assessment procedures to evaluate between group differences. Half the sample was randomly selected for magnetic resonance imaging (MRI). Neurologic examinations were conducted using the Neurologic Rating Scale (NRS). Neuropsychological measures included the Paced Auditory Serial Addition Test (PASAT), Rey Auditory Verbal Learning Test (RAVLT), Conners' Continuous Performance Test II (CPT II), and Halstead Impairment Index (HII) including the Booklet Category Test (BCT). Data were analyzed using linear regression. Participants with moderate/ severe TBI were significantly more likely to have trauma-related imaging findings, and more severe TBI predicted lower scores on the NRS. No significant between-group differences were identified on the HII, PASAT, RAVLT, or CPT II. TBI group performance was significantly better on the BCT. More severe TBI predicted abnormal imaging findings and lower NRS scores. Hypothesized between-group differences on neuropsychological measures were not supported.