We examined hypotheses proposed by System Justification Theory (SJT; Jost, Banaji, & Nosek, 2004) regarding intergroup evaluation in disadvantaged groups, using large samples of online participants (total N = 715,721), spanning 8 intergroup domains and 14 nations. Using a meta-analytic approach, we tested these hypotheses at the individual level (as SJT is generally articulated), as well as at the social group level. Consistent with SJT, individual-level analyses revealed that disadvantaged groups demonstrated outgroup favoritism on Implicit Association Tests (IATs; i.e., implicit measures), but demonstrated ingroup favoritism or no intergroup preference on self-report (i.e., explicit) measures. Additionally, these average effects were characterized by high heterogeneity, and follow-up exploratory analyses revealed that intergroup evaluation in disadvantaged groups was moderated by the intergroup domain: Whereas some disadvantaged groups consistently displayed outgroup favoritism (e.g., age, weight), others consistently displayed ingroup favoritism (e.g., sexual orientation, religion), and yet others displayed diverging patterns on implicit and explicit measures (e.g., race, ethnicity). Consistent with SJT, intergroup evaluation on all measures was moderated by self-reported conservatism. Furthermore, the magnitude of these relationships depended on the level of analysis, with small effects emerging at the individual level and medium-sized effects emerging at the social group level. Social group-level analyses also indicated that intergroup evaluation in disadvantaged groups was moderated by stigma. Overall, these findings support and extend the predictions of SJT, but the relatively complex patterns of intergroup evaluation in disadvantaged groups identified here illustrate a need for further theory development and more theory-driven research in this domain.