The importance of family background in determining a student's academic achievement has long been acknowledged by researchers. Nonetheless, the effect of schooling on this relationship has also been widely investigated. Some studies have shown that family background plays a far stronger role while the effect of schooling is minimal; others have found that schooling has much to do in either reinforcing or mitigating the effect of family background. Through analyzing the PISA (Programme for International Student Assessment) 2018 dataset for Taiwan, the present study explores the moderating effect of schooling on the relationship between family background and academic achievement. To understand the effect of schooling on the relationship between family background and academic achievement, the present study employs two-level hierarchical linear modeling to take into account the fact that in the PISA 2018 dataset, students are nested within classes, and classes are nested within schools. The results indicate that after taking into account school-level factors and their interaction with family background, the effect of family background on academic achievement diminishes significantly. Among the school-level factors examined in this study, the SES composition of the student body of a school appears to be the most significant predictor of academic achievement. Residence-based admissions and perceived teacher interest in students seem to play a role as well.