Abstract Although access to quality education in rural China has expanded dramatically over the past 3 decades, significant disparities persist between ethnic minorities and the Han majority. This article compares the academic achievement and determinants of achievement of minority and Han students in rural western China. In a survey of nearly 21,000 primary school students, we find that minority students score significantly lower than their Han peers on standardized exams in math and Chinese. This Han-minority achievement gap is largest for minority students whose primary language is not standard Mandarin (putonghua): these students score on average more than 0.6 standard deviations lower than Han students in both subjects. For minority students whose primary language is standard Mandarin, the gap with Han students is almost fully explained by different endowments of student, class peer, teacher, and school characteristics. Endowments of these characteristics, however, explain little of the achievement gap for non-Mandarin minority students. A fixed effects analysis also shows that the returns to Han students of attending individual schools tend to be larger than those to minority students with similar characteristics. Further, these school-specific differential returns to Han and minority students are most strongly associated with the characteristics of teachers.