The purpose of this study was to identify predictors of friendship quality in adolescents with and without ADHD. The participants were 115 adolescents (61 ADHD, 54 non-ADHD), ages 13-18. The adolescents completed questionnaires assessing the quality of their relationships with their best friends, social perspective taking, anxiety and depression. Their parents completed questionnaires assessing the adolescents' social skills, oppositional behaviors, and conduct problems. Being female was associated with higher levels of friendship quality. Although ADHD status did not predict friendship quality among 13-15 years old adolescents, having a diagnosis of ADHD was negatively associated with friendship quality among 16-18 years old adolescents. Friendship stability, anxiety, social perspective taking, and social skills were positive predictors of friendship quality over and above gender, age and ADHD status whereas oppositional behavior was a negative predictor of friendship quality. Social perspective taking mediated the relationship between friendship quality and anxiety and social skills mediated the relationship between oppositional behavior and friendship quality.