The purpose of this research is to improve our understanding of the determinants of obesity among children of Mexican origin. This is an important problem because obesity is widely prevalent among immigrants of Mexican descent and is associated with several medical conditions. The research will use NHANES III and ENN surveys for, respectively, the U.S. and Mexico to explain the outcomes for children between the ages of 2 months - 19 years. A major hypothesis is that children of parents who migrate from Mexico become obese due to poor health behavior and cultural attitude about weight. The empirical analysis will be useful for designing interventions aimed at reducing obesity.