The friendships of children displaying symptoms of attention-deficit/hyperactivity disorder (ADHD) have been understudied, particularly in comparison to the domain of peer rejection. This study tested whether friendship intimacy exchange buffers the prospective relation between ADHD symptoms and social problems one year later in a sample of children attending a community-based after-school program. Children (N = 131; 53% boys; 66% African American) ranging from 5 to 13 years of age participated in this study. At baseline, children reported on friendship intimacy exchange with their identified best friend, and program staff rated children on ADHD symptoms and social problems. Staff ratings of children’s social problems were collected again one year later. Multiple regression analyses indicated that, after controlling for demographic variables and baseline social problems, friendship intimacy exchange significantly moderated the association between ADHD symptoms and social problems at the one-year follow-up. Specifically, the relation between ADHD and social problems was no longer significant for children reporting high levels of friendship intimacy exchange. This moderation was not further qualified by either child age or sex, although boys were more likely than girls to report low rates of friendship intimacy exchange. These findings indicate the importance of friendship intimacy for children displaying ADHD symptoms, who often experience significant peer problems. Friendship quality may be a promising target for prevention and intervention efforts in mitigating some of the long-term social problems associated with ADHD symptomatology, and future research is needed to extend these findings to other domains of friendship quality and clinical samples of children with ADHD.