Many youth with autism spectrum disorder (ASD) experience comorbid emotional and behavioral difficulties that have a significant impact on their functioning (Kanne, Abbacchi, & Constantino, 2009). Parents and teachers are valuable informants in piecing together a better picture of these difficulties in the assessment process. However, parents and teachers often exhibit significant divergence on reports of the same behaviors on the same child. Research into parent-teacher discrepancies have aided in identifying how these discrepancies occur and how to extract useful information regarding contextual variation in behavior from these discrepant reports (e.g. De Los Reyes, 2011). However, research in this area is rather limited in terms of comorbid psychiatric symptomatology in youth with ASD and does not explain how discrepancies in this area may be related to core symptoms of ASD. This study examined whether the relation between behavioral and emotional symptoms and ASD symptoms, IQ, and adaptive skills was different for parent and teacher reports in 141 youth referred for ASD assessment. Overall, while results replicated findings that significant discrepancies exist between parent and teacher reports of comorbid behavioral and emotional symptoms, parent and teacher reports were not differentially related to ASD symptoms, IQ scores, or adaptive skills. Results of this study highlight that parent-teacher discrepancy of comorbid symptoms may not vary across different levels of functioning in youth with ASD, and that the measure used in this study to assess comorbid behavioral and emotional symptoms may functioning similarly across different youth with ASD.