This study examined whether social mistrust in early adolescence was general or referent-specific. We used a multi-trait multi-method approach to examine the validity of mistrust measures across social referents (mistrust toward people in general, toward peers, and toward teachers), using questionnaires and an online task. Sixth graders (N = 1243, ca. 11--13 years) in southern China reported about mistrust (i.e., general, teacher and peer), their social anxiety and aggression. Part of the students (N = 262) played an online trust game against a virtual, unfamiliar peer. Confirmatory factor analyses showed that mistrust was distinguishable across referents. All referents of mistrust were significantly associated with social anxiety and aggression, whereas only peer mistrust was associated with peer-trust behavior in the online game. As such, our findings may underscore the referent-specificity of mistrust in early adolescence. Insights for promoting healthy school adjustment were discussed.