The number of studies on school violence and bullying is increasing but research on the topic in Poland and other Central and Eastern European countries is in its early stages. This survey was answered by 904 Polish adolescents from six upper secondary schools in three cities. The results showed that victimization of any type was suffered by 18.7% of the participants, perpetration was reported by 13.1% of the students and a high percentage of students reported being perpetrators and victims at the same time (44.1% with mild and severe frequencies). Involvement in any bullying role was more common in boys and in technical and vocational schools. Victimization was related to lower academic performance. Occasional victims and students involved in both victimization and perpetration (victim/perpetrator) reported ignoring, telling friends or not doing anything when attacked. Fighting back was the most common reaction in severe victim/perpetrators. Only a small percentage of bystanders told the adults about bullying (5%) and only 38.6% never witnessed aggression towards peers. Given the small number of studies on the topic in this geographic area, it is necessary to conduct more research and compare findings among different studies. Violence is common in Polish schools and it is important to design and conduct interventions to eradicate it.