This study investigated the relationship between sufficient amounts of physical activity among Brazilian adolescents and the economic and social indicators of the cities where they live. Data from a large national survey including 109,104 boys and girls ages 13 to 15 yr. (47.8% boys, 52.2% girls) were analyzed. The economic and social indicators were the Human Development Index (HDI), which is a comparative measure to rank cities according to their degree of human development, the Gini index (income inequality), population density, and maternal education. Stepwise regression was used to identify associations between physical activity and economic and social indicators of the cities. The physical activity of Brazilian adolescents was associated with the social and economic conditions of the cities where they live. The amount of physical activity of girls was greater in the cities with fewer income inequalities. For boys, physical activity was greater in the cities with a higher HDI and fewer income inequalities.