This study evaluated psychometric properties of interview, self-report, and screening versions of the Child PTSD Symptom Scale for DSM-5 (CPSS-5), a measure of posttraumatic stress disorder (PTSD) for traumatized youth based on DSM-5 criteria. Participants were 64 children and adolescents (51.6% female, 45.3% African American/Black) between 8 and 18 years of age (M = 14.1, SD = 2.5) who had experienced a DSM-5 Criterion A trauma. Participants completed test-retest procedures for the self-report and interviewer versions of the CPSS-5 in 2 visits that were up to 2 weeks apart. Analyses revealed excellent internal consistencies, good to excellent test-retest reliability, and good convergent validity and discriminant validity for interview and self-report versions of the scale. Receiver operating characteristic analysis yielded a cutoff score of 31 on the CPSS-5 self-report version for identifying probable PTSD diagnosis. Six most frequently endorsed items by those with a possible PTSD diagnosis on the CPSS-5 were identified to constitute a screen version of the CPSS-5, showing good internal consistency and test-retest reliability. The three versions of the CPSS-5 scales are valid and reliable measures of DSM-5 PTSD symptomatology in traumatized youth.