Objective: Studies utilizing parent-report measures have identified above average levels of internalizing and externalizing problems in siblings of children diagnosed with ADHD. Scant research has examined siblings' self-report on standardized measures of emotional functioning. The current study examined parent-reported and child self-reported symptoms of siblings of children with ADHD compared with a control group. Method: Measures completed included the Children's Depression Inventory, the Multidimensional Anxiety Scale for Children, the Child Behavior Checklist and the Disruptive Behavior Rating Scale. Results: Parent-report measures indicated that siblings of children with ADHD had higher levels of internalizing, hyperactivity, and inattention problems compared with control siblings. Significant differences between groups were not revealed on child self-report measures. Conclusions: Although parent-report measures continue to demonstrate higher levels of symptoms for siblings of children diagnosed with ADHD compared with control siblings, there are no indications that self-reported internalizing symptoms are different. (Contains 2 tables.)