["Journal of Research on Adolescence, Volume 36, Issue 2, June 2026. ", "\nAbstract\nThis longitudinal study investigates the bidirectional relationship between personal values and aggressive behavior among immigrant adolescents from the Former Soviet Union residing in Israel. Using a 4‐wave cross‐lagged latent difference score modeling approach over 2 years, we examined the reciprocal associations between personal values and aggressive behaviors over time. The sample included 180 adolescents (mean age = 14.36 years, SD = 1.35; 44.5% girls) and their primary caregivers, with youth reporting on personal values and both youth and parents reporting on adolescent aggression. Separate models were estimated for youth‐ and parent‐reported youth aggression. Our findings indicated that immigrant youth aggression predicted changes in personal values over time, but not vice versa. For youth‐reported models, adolescents' aggressive behavior predicted increases in self‐enhancement and openness to change values and decreases in self‐transcendence and conservation values. For parent‐reported models, youth aggressive behavior predicted increases in youth self‐enhancement values over time. These results highlight the asymmetry in the value‐behavior dynamic during adolescence, particularly as immigrant youth navigate and integrate into a new socio‐cultural environment. Our findings highlight the role of behavioral adaptation in shaping value systems during adolescence, offering insights into mechanisms underlying immigrant youth adjustment. Our findings emphasize the importance of targeting aggressive behaviors in interventions to foster adaptive values and enhance social integration.\n"]