This article examines whether longitudinal reading trajectories vary by the generational status of immigrant children as they begin formal schooling through the 3rd grade. The results of the hierarchical linear model indicated that 1st and 2nd generation children (i.e., those born in a foreign country and those born in the United States to foreign-born parents, respectively) had higher achievement scores at the spring of kindergarten than did 3rd generation children. Yet, controlling for race/ethnicity and maternal education fully reduced the 1st generation advantage. In addition, 1st generation children grew in reading achievement at a faster rate than did 3rd generation children. Controlling for a host of proximal and distal factors that included demographic, race/ethnic, family, and school characteristics somewhat reduced the association between generational status and rate of growth. First and 2nd generation children continued to increase their reading scores at a faster rate than did 3rd generation children. It is likely that additional factors not measured in the Early Childhood Longitudinal Survey-Kindergarten cohort, such as selection, cultural, or motivational factors, would be useful in further explaining the immigrant advantage. (Contains 4 tables and 1 figure.)