This review examined the relations between grit and academic achievement based on a meta-analysis of 137 studies yielding 156 dependent samples (N = 285,331). Using the robust variance estimation, we found that the correlations of overall grit level with academic achievement were generally weak to moderate (weighted r = 0.19). The correlation of perseverance of effort to achievement (weighted r = 0.21) was stronger than that of consistency of interest (weighted r = 0.08). Adopting a cross-cultural perspective in reviewing these findings, we concluded that the associations between overall grit/2 facets and academic achievement did not differ across individualism-collectivism. We also investigated 7 other moderators, including grit measurement, types of achievement measures, publication type, educational levels, research design, study quality, and the female ratio of sampling in the grit-achievement relationship. After controlling for all proposed moderators, no significant moderators were found in the overall grit-achievement link or the consistency of interest-achievement link. There was a significantly stronger association between perseverance of effort and academic achievement in nonstandardized measures than in standardized measures. Theoretical and practical implications are discussed.