This study examined the relationship of instrumental and emotional aggression to bullying, victimization, and psychosocial maladjustment. It was hypothesized that both types of aggression would be associated with bullying behavior and that emotional aggression would be exclusively associated with risk of victimization and psychological maladjustment (that is, depression, anxiety, and loneliness). The sample consisted of 219 Taiwanese seventh-graders with valid data on all of the research variables; 51.1% (n = 112) were male, and 48.9% (n = 107) were female. A series of structural equation models was analyzed to evaluate fit indices for competing models. The results indicated that both instrumental aggression and emotional aggression were associated with bullying, but only the latter was associated with victimization. Once psychological maladjustment was entered into the model, the association between emotional aggression and bullying became nonsignificant. Model indices also suggested that psychological maladjustment was a concurrent characteristic rather than a consequence of peer victimization. Implications for future investigation are discussed.