The objective of the current study was to examine possible risk (school-bullying and victimization, exposure to media violence, callous-unemotional traits, impulsivity and narcissism) and protective (family, peer and school social support) factors that might be associated with cyberbullying and cyber-victimization by employing a longitudinal, two-wave design. The sample consisted of 1,416 (50.1% girls) adolescents living in Cyprus. The findings suggested cross-sectional and longitudinal associations between school-bullying and cyberbullying and between school-victimization and cyber-victimization. Furthermore, callous-unemotional traits were longitudinally related to cyberbullying. Media violence exposure was a risk factor leading to both cyberbullying and cyber-victimization, while family social support was a protective factor for both types of adjustment problems. Finally, family social support protected adolescents living in single-parent households from being cyber-victimized when their friendships were not supportive.