Poverty levels among all children in the United States have tended to fluctuate in the past 30 years. However, among the children of immigrants, child poverty increased steadily and rapidly from about 12% in 1970 to 33% in the late 1990s before declining to about 21% in 2000. Using 1970, 1980, 1990, and 2000 Public Use Microdata Samples data, we identified key factors that underlie the fluctuations in immigrant child poverty from 1969 to 1999 and the divergence from children of natives. We found that roughly half the absolute increase in immigrant child poverty can be linked to changing conditions in the U.S. economy that make it more difficult to lift a family out of poverty than 30 years ago. These changes occurred disproportionately among children of parents with lower levels of education, employment, and U.S. experience but not among racial/ethnic minorities. Poverty risks among various racial and ethnic groups converged over time. The relative increase in poverty for immigrant versus native children owes largely to the divergence between immigrant and native families in racial/ethnic composition, parental education, and employment.