Assessment of clinical symptoms requires information from multiple informants. Discrepancies between informants' ratings can have significant implications in school settings (e.g., access to services, treatment planning, progress monitoring). This study examined parent-teacher discrepancies for ratings of internalizing and externalizing symptoms, and adaptive skills of high-functioning children with autism spectrum disorder. A total of 236 Behavior Assessment System for Children-2nd Edition ratings of children with high-functioning children with autism spectrum disorder from 2 informant groups (parents and teachers) were analyzed. Each informant pair (n = 118 parents/caregivers and n = 118 teachers) rated the same child. Scores on the Internalizing Problems, Externalizing Problems, and Adaptive Skills Composites were examined for mean differences, level of agreement, linear relationship, and moderators of discrepancies. There were no significant mean differences between raters for the Internalizing and Externalizing Composites or their constituent scales (except Hyperactivity). Parent-teacher ratings on these composites and scales were significantly correlated (generally moderate), and the discrepancies were not moderated by the included child or parent variables. In contrast, teacher ratings were significantly higher than parents for the Adaptive Skills Composite and several of its constituent scales. Correlations between informants on the Adaptive Skills Composite were significant (low-to-moderate), with notable variability in the correlations among its constituent scales. The degree of parent-teacher discrepancy differed significantly across the Adaptive Skills Composite score range, but it was not moderated by the included child or parent variables. This study suggests a reduced likelihood of informant discrepancies for externalizing and internalizing symptoms, with larger discrepancies expected when assessing adaptive skills.