The aim of this study was to investigate the relationship between built and social environment and leisure-time physical activity (LTPA) among adults living in an urban center. The individual data was from the household survey and the environmental data was assessed through systematic social observation by trained observers on street segments of respondents' residences. The relationship between environmental factors and LTPA was examined using multilevel logistic regression. The prevalence of LTPA was 30.2% (95% CI 27.4-32.9%). Individuals living in census tracts with higher walking environment indicators (OR = 1.20; 95% CI 1.02 to 1.40) and safety (OR = 1.18; 95% CI 1.01 to 1.38) were more likely to be active during leisure time, even after adjusting for individual variables. Improving the built and social environment is an important step for achieving higher levels of LTPA in the population in a middle-income country.