Childhood obesity not only has serious long-term health implications but also can hinder the development of socioemotional skills. We use data from the Longitudinal Survey of Australian Children to examine the effect of childhood obesity on socioemotional difficulties. Using various specifications to estimate the socioemotional-skills production function, we show that obesity increases emotional problems for both genders and increases peer problems and decreases conduct problems for boys. Obesity does not appear to affect hyperactivity or prosocial behavior. Our results are robust to alternative identifying assumptions, the inclusion of a range of time-varying shocks, and alternative measures of adiposity. Our findings suggest that childhood obesity adversely affects emotional and social skills, which are both important determinants of human capital development and future economic prosperity.