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Quality results depends on the available data accuracy. Topographic data for the entire globe from SRTM - Shuttle Radar Topography Mission are free and, if correct, they represent a powerful resource for the territorial and environmental planning. However, its use, in models for information systems, must be evaluated in order to assess the information reliability. The aim of this study was to verify the similarity between a soil loss map generated from SRTM DEM and another from a higher resolution. USLE model - Universal Soil Loss Equation was applied with the intention of estimate soil loss rates in a basin on the northeast of Sao Paulo State in Brazil. Therewith it was possible to assess the performance of SRTM DEM. The similarity was checked using the Kappa index, which shows the degree of similarity between maps through an error matrix. The Kappa index revealed that SRTM DEM has an accuracy level considered reasonable (0.6594), while Kappa values for LS factor (0.2584), natural erosion potential (0.2582) and estimated soil loss (0.4199) accuracy levels are considered low, low and moderate, respectively. Therefore, this study showed that the application of SRTM DEM can offer satisfactory results when multiplied by higher quality data in basins where LS is not a decisive factor in estimated soil loss, but must be used carefully in other conditions.