Cyberbullying is a growing problem among adolescents and adults alike. To date, research concerning cyberbullying has focused on Europe and the Anglophone countries. This study contributes to understanding of cyberbullying by adding the case of adolescents in Japan. Participants were 899 high school students who completed a self-report questionnaire on technology use habits, cyberbullying and cybervictimization experiences. Logistic regression analyses were used to measure the relationship between cyberbullying, cybervictimization and several independent variables, including gender, age and technology use. Results showed that 22% of the participants had experienced cybervictimization, while 7.8% admitted to cyberbullying others. Most cyberbullying cases involved classmates and the victims knew the identities of their tormentors. Multiple logistic regression analyses revealed that cybervictimization is the biggest significant predictor of cyberbullying and vice versa. Having more online friends was significantly associated with cyberbullying and cybervictimization. To cite this document: Â Reinis Udris, "Cyberbullying in Japan: An exploratory study", International Journal of Cyber Society and Education, Vol. 8, No. 2, pp. 59-80, 2015. Permanent link to this document: http://dx.doi.org/10.7903/ijcse.1382