Abstract Introduction: The use of social media tools is increasing day by day. In addition to its positive use, social media tools are also used in the virtual environment to harm others. This harmful use is noted as cyber-bullying. Determining the factors affecting cyber-bullying is of great importance in terms of contributing to intervention studies. This study aims to examine the moderate role of positivity and sensitivity towards cyber-bullying between cyber-victimization and cyber-bullying. Methods: The study was carried out with 342 university students, who approved voluntary participation in the process. The students who voluntarily participated in the research were 239 females (69.9%) and 103 males (30.1%), who were between 18 and 28 years old. In the data collection process, the revised cyber-bullying inventory, positivity scale, and personal information forms were used. In this research process, the moderating role of positivity and sensitivity (M) in the relationship between cyber-victimization (X) and cyber-bullying (Y) was investigated. Results: As a result of the research, it was found that 35% of the participants were exposed to cyber-bullying and 1.4% were engaging in cyber-bullying. It was also found that there was a moderate positive relationship between cyber-victimization and cyber-bullying. In addition, the results showed that there is a negative relationship between positivity and sensitivity to cyber-bullying and cyber-victimization, and cyber-bullying. As a result of the analysis, it was observed that positivity and sensitivity affected the relationship between cyber-victimization and cyber-bullying. The results indicate that a decrease in positivity and sensitivity results in cyber-bullying behaviour, whereas an increase in positivity and sensitivity decreases cyber-bullying behavior. Discussion: The concept of positivity can be said to enable individuals exposed to cyber-bullying to create alternative emotions and create alternative strategies for the problem they are experiencing. In addition, the high level of positivity of the individual experiencing cyber-victimization can be thought to help develop and maintain friendship relations by improving their psychological resources. As a result, it can be stated that the probability of cyber-bullying decreases. In another result of the research, it has been revealed that the sensitivity between exposure to cyber-bullying and cyber-bullying has a moderating effect on cyber-bullying. When the sensitivity to cyber-bullying is low, it is observed that the effect of cyber-victimization on cyber-bullying is further increased. When there is a high sensitivity to cyberbullying, the impact of cyber-victimization on cyber-bullying is increasing very little and this effect is observed to be less powerful. Limitations: The current study has also some limitations. First, the study was carried out as a cross-sectional study. A longitudinal study can be conducted to obtain more detailed results about the moderating effect. Second, positivity was used as an indicator of well-being. Therefore, it is essential to be careful while generalizing the results; different scales related to psychological well-being can be used. Third, the current study just used scales to evaluate the students’ self-report; for this reason, the choice of mixed research approaches can offer a wide perspective by taking the opinions of different individuals such as friends and parents of individuals. Conclusions: The findings provide evidence for reducing cyberbullying. In addition, the results provide useful information in the preparation of cyberbullying intervention programs.