Youth with autism spectrum disorder (ASD) often present with emotional problems such as anxiety and depression (American Psychiatric Association, 2013). A recent study of the "Child Behavior Checklist 6-18" (CBCL; Achenbach & Rescorla, 2001) indicated good sensitivity but relatively low specificity for identifying emotional problems in youth with ASD. The current study examined the extent to which variance in the CBCL's "Anxious/Depressed," "Withdrawn/Depressed," "Internalizing Domain," and "Total Problems" scales was accounted for by symptoms of emotional problems relative to ASD symptoms. Correlation and multiple regression analyses indicated that these scales measured anxiety and depression but a small statistically significant proportion of variance in Total Problems scores was also accounted for by ASD symptoms. Results contribute to the emerging evidence base for the inclusion of the CBCL in assessment protocols for assessing emotional and behavioral problems in youth with ASD.