Research suggests that cyberbullying is more harmful than traditional bullying and can cause more profound harm to individuals. The study aimed to examine the effects of cyberbullying victimization on junior high school students' cyberbullying over time while exploring the mediating role of loneliness and the moderating role of perceived social support. Four self-report questionnaires were administered to 561 middle school students at three time points. Data were analyzed using SPSS for descriptive statistics and Pearson correlation analysis. Moderated mediated effects tests were performed on the variables using SPSS Process. T1 cyberbullying victimization in middle school students predicts T2 cyberbullying behavior. T2 loneliness mediates the role of T1 cyberbullying victimization in influencing T2 cyberbullying. T2 perceived social support moderated the second half of the mediating role pathway. First, there are many mediators and moderators of cyberbullying victimization that affect cyberbullying, and others need to be examined. Second, only three middle schools in China were selected as investigators for this study, and future studies could select different populations to verify the applicability of the findings. Cyberbullying victimization can increase cyberbullying. Reducing cyberbullying requires attention to psychological and behavioral changes in cyberbullying victims.