Recent research suggests that children may encounter aggressive behaviour during the transition from preschool to school. Yet, relatively few longitudinal studies have been conducted on children's perceptions of aggressive behaviour in the transition from preschool to school. This study aims to fill a major gap in the literature by exploring Chinese children's perceptions and experiences of aggressive behaviour, and their ways of coping with aggression, at three points in time: during the last month at preschool (Time 1), the first three months of Year 1 at school (Time 2) and the last month of Year 1 (Time 3). The present study also examines the role gender plays in 79 Chinese children's perceptions of aggressive behaviour, as depicted in their drawings and accompanying narratives. The children mainly reported physical and verbal aggression rather than relational aggression. The findings provide robust data for understanding how children cope with aggression at school.