The academic achievement gap between racial and ethnic majority and minority students in South Korea has received attention over the past decade, with one government-funded report and 10 peer-reviewed articles examining the performance of diverse student groups in the 2011 National Assessment of Educational Achievement. We conducted a qualitative content analysis of these 11 studies to understand how the evident achievement gap is explained by researchers and what assumptions are embedded in these explanations. Using multicultural education paradigms as theoretical lenses, we classified the explanations and advanced understanding; findings indicated that the cultural deprivation paradigm dominated the discussion of the academic performance of ethnic minority students. While other explanations were also found, some of these reinforced stereotypes about ethnic minority groups without corroborating evidence. Emergent efforts to address the strengths of ethnic minority students were insufficient to reflect the authentic view of the cultural difference paradigm. Implications were drawn for researchers and educators who study academic achievement gaps between ethnic minority and majority students in multicultural societies.