["Journal of Research on Adolescence, Volume 36, Issue 2, June 2026. ", "\nAbstract\nThis three‐wave longitudinal study examined the relations between moral judgment of aggression and defending behaviors, with a focus on the moderating effects of self‐reported and peer‐nominated victimization. Participants included 1183 elementary‐school students (Mage = 10.88 years, SD = 0.86; 43% girls, 57% boys). Results from random intercept cross‐lagged panel models revealed reciprocal effects between moral judgment of aggression and defending behaviors at the within‐person level, moderated by self‐reported victimization. Specifically, stronger‐than‐usual moral judgment of aggression more strongly predicted higher‐than‐usual subsequent defending behaviors when adolescents self‐reported higher‐than‐usual victimization. In contrast, higher‐than‐usual defending behaviors predicted stronger‐than‐usual subsequent moral judgment of aggression only when adolescents self‐reported lower‐than‐usual victimization. Peer‐nominated victimization and gender did not show moderation effects. These findings emphasize the importance of fostering a positive cycle between moral judgment of aggression and defending behaviors, especially when supporting victimized adolescents.\n"]