Ostracism can lead to strong behavioral responses, including diminished prosocial behavior. To date, experimental research examining this effect has only been conducted with adults. The current study consisted of 40 adolescents, half of whom were experimentally ostracized using the Cyberball paradigm. Participants' subsequent levels of pronounced prosocial behavior were measured, and personality traits were examined as possible moderators in participant behavioral responses. Results revealed that, compared to controls, ostracized adolescents showed less prosocial behavior, and this was moderated by having an "open" personality.