Attention-deficit hyperactivity disorders (ADHD) and posttraumatic stress disorder (PTSD) are the most commonly diagnosed disorders in sexually abused children (SAC). There is a high degree of symptom overlap and comorbidity between these disorders, and differential diagnosis can be confusing. Current diagnostic criteria do not include PTSD as a differential diagnosis for ADHD, nor do existing assessment guidelines address these diagnostic similarities. This may have serious implications for SAC. This literature review describes the psychological impact of child sexual abuse and possible consequences for misdiagnosing ADHD in SAC. A comparison of criteria from the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (American Psychiatric Association, 1994) criteria for ADHD and PTSD is presented, and commonalities are discussed. On the basis of this comparison, recommendations are made for improving clinical decision-making and for facilitating differential diagnosis. Routine inquiry about traumatic experiences in children presenting with ADHD symptoms is suggested to increase accuracy in differential diagnosis.