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The objective of this study is to assess the climate simulations and projections over South America using the regional climate Eta Model driven by fully coupled Earth System Model HadGEM2-ES of the Met Office Hadley Centre. The HadGEM2-ES was designed to run the major scenarios for IPCC AR5 and comprises Earth system components such as terrestrial and ocean carbon cycle and tropospheric chemistry. Over the past years the regional climate Eta Model has been used to produce climate change scenarios over South America (Pesquero et al. 2009, Chou et al. 2012, Marengo et al. 2012). In this study, Eta model was configured with 38 vertical layers, 20-km grid size and was run over 19602005 based on historical emissions, and 20062100 based on RCP4.5 scenarios to simulate possible future changes. We have evaluated the regional climate simulation for some areas in Brazil, particularly for Amazon and Northeast, Southeast and South regions of Brazil. Annual cycle of precipitation and surface temperature for these areas was compared with CRU (Climatic Research Unit) observational data. Simulated and projected patterns of mean fields of precipitation, temperature and upper and low-level circulation were analyzed for austral summer and winter. The regional model reproduces reasonably well the spatial patterns of the precipitation and temperature. The downscaling with Eta model improved the simulation of the seasonal cycle of precipitation and temperature over Brazil and some regions when compared with HadGEM2-ES. The projections suggested increases in DJF and JJA temperature of up to 4 °C in continental South America, with more intense changes occurring in the second half of the twenty-first century. The precipitation projections showed the major changes in summer.