The purpose of this short-term longitudinal study was to examine Chinese children’s trajectories of physical and relational aggression and their association with social-psychological adjustment problems (i.e., depressive symptoms and delinquency) and gender. Fourth and fifth grade children in Taiwan (n = 739, age 9–11) were followed across 1 year. Results of Linear Mixed Models demonstrated that, on average, relational aggression increased in a linear fashion for fifth grade children and girls and physical aggression remained stable for boys and increased linearly for fifth grade girls. Further, increases in relational aggression were associated with time-dependent increases in depressive symptoms, and the effect size of this association seemed to be stronger than that of physical aggression. Findings are discussed in the context of Chinese culture.