The current study evaluated the psychometric properties of the Comprehensive Trauma Interview Post-Traumatic Stress Disorder (PTSD) Symptoms Scale (CTI-PSS), a novel method of assessing PTSD symptoms following exposure to a range of child adversities in the child maltreatment population. A sample of female adolescents (n = 343) exposed to substantiated child sexual abuse and a nonmaltreated comparison condition completed the CTI-PSS and other established measures to assess internal consistency, factor structure, test discriminability as well as convergent, discriminant, and incremental validities. Results demonstrated that the CTI-PSS is a reliable and valid measure of PTSD symptoms with good discriminability and a factor structure that fits existing conceptualizations of the PTSD construct. It also demonstrated strong convergence with an established measure of PTSD symptoms and explained unique variance in the prediction of child sexual abuse status. Overall, the CTI-PSS appears to be a useful instrument for assessing PTSD symptoms in the child maltreatment population.