School transitions provide contexts for adolescents to reconstruct peer relationships and re-establish social positions. Scarce research has captured the transition of aggressor and victim roles during this period and examined associated factors. To investigate the stability and shifts of aggressor and victim roles following the transition to middle school, this study conducted latent transition analysis with 1261 Chinese adolescents (32.6% female, Mage in Grade 6 = 12.1 years, SD = 0.7). Three subgroups were identified across Grades 5 to 8: aggressive-victims, victims and uninvolved. Adolescents were more likely to transition from aggressive-victim and victim roles to the uninvolved group during the transition to middle school compared to the transitions within the same educational phase. Males and those with insecure parental attachment were at higher risk of being and remaining in the involved groups. The findings underscore the dynamic nature of adolescent aggression and victimization and highlight the transition to middle school as a critical window for interventions aimed at helping adolescents disengage from aggression and victimization.