© 2018 American Psychological Association. Although the neural correlates of social exclusion have been well-documented, most studies have examined single age groups. No studies have directly compared specific age-related differences in social exclusion across children, adolescents, and adults using event-related oscillatory electroencephalogram (EEG) dynamics. The authors examined event-related theta EEG power and phase coherence in fair play and social exclusion conditions during the Cyberball task in 166 participants: 42 children (ages 1012), 56 adolescents (ages 1417), and 68 adults (ages 1828). Children and adolescents displayed the greatest theta power to rejection events, whereas adults displayed the greatest theta power to not my turn events. Moreover, the functional link between theta power to rejection and self-reported distress was strongest among the adolescents. These findings suggest that an enhanced neural response to social exclusion is present by preadolescence, but the association between neural and subjective responses is most prominent during adolescence.