Using data obtained through the Arizona Child Fatality Review Program, we reviewed deaths of all children (birth-17 years) who were Mexican or Central American residents and who died in Pima County, Arizona during the years 1995–2004. They accounted for 5% of all pediatric deaths in the county. Causes of death were motor vehicle collision (32%), environmental exposure (17%), prematurity (11%), other trauma (11%) and other medical conditions (28%). Fifty-three percent of these children were in the US seeking medical care; 36% were undocumented migrants. Significant trends over the 10 years were toward fewer children seeking medical care and more children dying while border crossing. Border health and economic disparities affected overall child mortality in this US county, but current prevention efforts are unlikely to affect this population group.