There is growing interest in the role of emotional competence in middle school children's adjustment and functioning, yet many populations remain underresearched. Few studies have explored the emotional competence, especially emotion understanding, of children with, or at risk of, attention deficit hyperactivity disorder (ADHD), and even fewer have examined the role emotion understanding plays in these children's social skills. Our study investigates a profile of the emotion understanding capacities of Israeli boys at risk of ADHD and evaluates its association with their social skills. One hundred and fifty-two boys (grades 4–6) were each assigned to an at-risk (n = 66) or comparison (n = 86) group based on their scores on an ADHD symptoms questionnaire (Conners Rating System–Revised). The two groups were matched on age, socioeconomic status and class, and school environment. Group comparisons revealed that relative to their non–at-risk counterparts, at-risk boys demonstrated less mature emotion understanding. Finally, our findings indicate that poor emotion understanding plays a more notable role in the social functioning of at-risk than non–at-risk children. This study's contribution to the understanding and school treatment of children with ADHD emotional and social competencies is discussed. © 2009 Wiley Periodicals, Inc.