A short-term longitudinal study during early childhood (N = 301; 155 girls; M = 44.76 months old, SD = 8.20) investigated the prospective associations between peer victimization and aggression subtypes. Specifically, observations of relational and physical victimization as well as teacher reports of the forms (i.e., relational and physical) and functions (i.e., proactive and reactive) of aggression were collected at two time points during an academic year. Within- and between-group gender differences were examined as part of the preliminary analyses. In order to address key study questions, both directions of effect between peer victimization and aggression subtypes were examined. We found that teacher-reported proactive relational aggression predicted decreases in observed relational victimization over time, whereas reactive relational aggression predicted increases in observed relational victimization over time. Ways in which these and other findings extend the literature are discussed.