At least half of the well-documented achievement gap for low-income Black children is already present in kindergarten, due in part to limited opportunities for acquiring foundational skills necessary for school success. There is some evidence that low-income minority children from immigrant families have more positive outcomes than their non-immigrant counterparts, although little is known about how the immigrant paradox may manifest in young children. This study examines foundational school readiness skills (academic and social-emotional learning) at entry into pre-kindergarten (pre-k) and achievement in kindergarten and second grade among Black children from low-income immigrant and non-immigrant families (N=299). Immigrant and non-immigrant children entered pre-k with comparable readiness scores; in both groups, reading scores decreased significantly from kindergarten to second grade and math scores decreased significantly for non-immigrant children and marginally for immigrant children. Regardless of immigrant status, pre-k school readiness and pre-k classroom quality were associated with elementary school achievement. However, declines in achievement scores were not as steep for immigrant children and several predictive associations were moderated by immigrant status, such that among those with lower pre-k school readiness or in lower quality classrooms, immigrant children had higher achievement test scores than children from non-immigrant families. Findings suggest that immigrant status provides young Black students with some protection against individual- and classroom-level risk factors for early underachievement in elementary school. (author abstract)