AbstractCyberbullying has increased in recent years due to the uptake of internet use by youth. One psychological process that has been consistently related to cyberbullying is moral disengagement. It is a process that is used to justify cyberbullying behavior as it enables the perpetration of cyberbullying without the perpetrator feeling guilt or remorse. A factor that may mitigate the use of moral disengagement is self-reflection and calmness that characterizes mindfulness. To address this possibility, this study investigated the role of mindfulness as a moderator of the association between moral disengagement and cyberbullying perpetration. Participants were 586 ethnically diverse youth aged between 10 and 16 years of age. Results revealed that mindfulness moderated the association between moral disengagement and cyberbullying perpetration. The relationship between moral disengagement and cyberbullying perpetration was weaker at high than at low levels of mindfulness. The findings suggest the potential benefits of including mindfulness training in anti-bullying intervention programs to decrease the prevalence of cyberbullying perpetration.