<p>Children/adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD) experience challenges in social functioning, however, the extent to which these challenges differ between males and females with ADHD is unclear. This scoping review mapped the existing literature examining social functioning among males and females with ADHD and within sex differences (i.e., comparing females with ADHD to females without ADHD) in childhood and adolescence. Fifty-one studies were included, and findings were synthesized using descriptive thematic analysis across multiple domains of social functioning (e.g., friendships, peer victimization). The evidence base was characterized by methodological heterogeneity including male-dominated samples, and inconsistency in social functioning measures and measures of sex/gender used. The current literature suggests that males and females with ADHD experience more social functioning challenges compared to their same-sex peers without ADHD. However, evidence examining sex differences in ADHD populations was mixed. Some studies found that females experience greater difficulties in peer relationships, conversely many studies found no sex differences across domains. These findings highlight gaps in the literature (e.g., domains of social support, and loneliness) and the need for developmentally informed, sex-specific, longitudinal research. Future research should seek to provide understanding on how social functioning develops from childhood to adolescence for males and females with ADHD.</p>