Background: Adolescents’ exposure to new communication systems via the Internet and mobile phone can be detrimental if cyberbullying is the case. Objectives: The present study aimed to investigate the prevalence of cyberbullying and detect its contributing factors. Materials and Methods: This cross-sectional study was performed in four girls’ and boys’ high schools in District 17, Tehran, Iran. The research sample was selected using the simple random sampling method. The research instrument was a researcher-made questionnaire encompassing three sections (namely, the experience of being cyberbullied, the experience of attempts at cyberbullying, and close friends’ exposure to cyberbullying). Results: Eighty-five of the respondents (29.82%) had experienced being cyberbullied, 89 persons (30.90%) had made attempts at cyberbullying, and 117 individuals (40.62%) had friends being cyberbullied. Female gender and secondary high school education significantly increased the likelihood of attempts at cyberbullying and being cyberbullied (P < 0.001). Moreover, there was a significant relationship between an increase in time to use virtual tools per week and aging with attempts at cyberbullying (P < 0.001). There was also a significant relationship between being cyberbullied and attempts at cyberbullying (P < 0.001). Conclusions: According to the study findings, the authorities are recommended to implement appropriate educational programs to increase adolescents’ awareness of cyberbullying and culturalization to exploit new communication tools at the school and community levels.