This study examines how multiple indicators of adolescent and parent acculturation relate to longitudinal trajectories of Latino adolescent aggression. The hierarchical linear modeling analysis is based on a final sample of 256 adolescents paired with one parent. Of the adolescents, 66% were born outside of the United States and the remaining 34% were US-born. Families lived in two sites: 38% lived in North Carolina and 62% lived in Arizona. The overall trajectory of Latino adolescent aggression displays a statistically significant negative trend best characterized by a quadratic curve. We delineate significant risk factors related to aggression levels, and show that gender, age, parent-reported acculturation conflicts, and adolescent-reported parent-adolescent conflicts are associated with higher levels of adolescent aggression. We discuss the study limitations, implications of the findings, and fertile ground for future research.