We examine the relationship between socio-economic factors and public opinion on environmental policies in Brazil, drawing on a survey conducted in June 2012. There are few systematic studies of the determinants of environmental preferences in emerging economies, and Brazil is a particularly interesting case because of its democratic political system, rapid economic growth, and importance for the global environment. In general, we find that the Brazilian public is highly supportive of environmental protection. To explain variation in environmental preferences, we focus on the effects of income and education. Many previous studies suggest that both should have positive effects, but the empirical evidence is mixed. Indeed, we find that income has no effect on environmental preferences. However, education is a strong predictor of environmental preferences. While college education is not necessary for environmental awareness, there is a large difference between Brazilians with primary and secondary education. For policy, the findings imply that investment in secondary education can raise environmental awareness, regardless of income levels.