This meta-analysis examined main effects and heterogeneity in associations between popularity and academic adjustment in the U.S. and China across 41 studies. The aggregated sample included 22,151 children and adolescents (10,934 boys; 11,217 girls) from both countries, with U.S. students from various ethnic backgrounds. Results in the U.S. were characterized by developmental differences, with popularity positively linked to academic functioning only in childhood (r = 0.26) but not adolescence (r = 0.01). Conversely, popularity was consistently related to academic adjustment in China across developmental stages (overall r = 0.36). Patterns in both nations were unaffected by other demographic meta-moderators but shifted after social acceptance was partialled out. Observed cross-national differences should be interpreted with caution, and potential caveats were discussed.