The authors examined the relation between early adolescents' trust beliefs in peers and both their attributions for, and retaliatory aggression to, peer provocation. One hundred and eight-five early adolescents (102 male) from the United Kingdom (M age = 12 years, 2 months, SD = 3 months) completed the Children's Generalized Trust Beliefs in peer subscale (K. J. Rotenberg, C. Fox, et al., 2005) and reported the intentions of, and their retaliatory aggression to, hypothetical peer provocation. A curvilinear relation was found between trust beliefs in peers and retaliatory aggression but not for attributions of intention. Early adolescents with low and those with very high trust beliefs in peers reported greater retaliatory aggression than did early adolescents with the middle range of trust beliefs. The findings supported the conclusion that early adolescents who are high trusting, as well as those are very low trusting, are at risk for psychosocial maladjustment. Support was not obtained for a hostility attribution bias interpretation of those patterns. (Contains 1 figure.)