The use of information and communication technology (ICT) has led to new risks, and among them is cyberbullying. It is important to be aware of the prevalence of cyberbullying in order to design intervention plans based on real contexts. Studies, however, vary widely in the data they report. These discrepancies may be due to differences in measurement. The main aim of our study, conducted in the Region of Murcia (Spain), was to ascertain the prevalence of cyberbullying in the three roles involved: victim, perpetrator and bystander. A descriptive, correlational and quantitative study was conducted using a “Cyberbullying: peer harassment screening”questionnaire to collect data. The representative sample comprised 950 students aged between 11 and 18 years (M = 13.93, SD = 1.35). The data showed that 72.1% of the participants had been involved in one or more cyberbullying situation (as victim, aggressor and/or bystander) in the previous year. Specifically, 49.3% had been cybervictims, 23.3% cyberaggressors and 62.3% cyberbystanders. The study provides detailed information about the prevalence of cyberbullying in the Region of Murcia and enables comparisons of the three roles involved. The data point to the need to promote active prevention and psychoeducational intervention strategies.