With the technological advances and significant development in the areas of remote sensing and geoprocessing, not only the production of maps, but also the geographic analysis was optimized and increased with significant quality gains. The analysis of morphometric parameters in watersheds constitutes an important task for the understanding of processes and environmental planning in this study unit, and the use of information obtained from Digital Elevation Models (DEMs) emerges as an interesting alternative for these analyses. Considering the advances in the availability and also in the handling of DSMs, this study performed a comparative analysis of the DSMs performance in the automatic obtaining of physical parameters of the Guassupi stream watershed, located in the central portion of the state of Rio Grande do Sul - BR. Four Digital Elevation Models were compared, being one originated from the interpolation of information from topographic maps at scale 1:50,000, one from the TOPODATA project and the two originated from SRTM, bands C and X, with approximate resolution of 30 meters.