This study was undertaken to investigate the relationship between internet addiction and online self-disclosure with the experience of cyberbullying-victimization among upper secondary school students in Roshtkhar County, Khorasan Razavi Province. The research follows a descriptive-correlational design. The statistical population comprised 3,000 students enrolled during the second semester of the 2021-2022 academic year. Based on the Morgan Table, a sample of 246 students was selected using cluster sampling. Data collection instruments included the Cyberbullying-Victimization Questionnaire (Antoniadou et al., 2016), the Young Internet Addiction Test (1996), and the Online Self-Disclosure Scale (Valkenburg & Peter, 2007). Data were analyzed using Pearson correlation coefficients and simultaneous regression analysis via SPSS version 26. The results indicated a significant relationship between internet addiction, online self-disclosure, and cyberbullying-victimization among students. Specifically, internet addiction predicted 34% of the variance in cyberbullying and 32% in cyber-victimization. Online self-disclosure predicted 31% of the variance in cyberbullying and 28% in cyber-victimization. These findings highlight the critical role of internet addiction and online self-disclosure as predictors of cyberbullying and victimization. The results offer significant implications for professionals and families who play a vital role in managing digital environments.