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Terrain is a main environmental factor which affects the surface hydrology and soil erosion. Slope steepness, slope length and LS factor are important parameters in soil erosion model. As a water conservation measure, terraced field changes the surface morphology and affects slope steepness, slope length and LS factor. Terrain features of the terraced area based on low resolution DEM are fuzzy and difficult to be reasonably estimated due to the lacking of high precision. High resolution DEM, which was accessed by UAV aerial photogrammetry technology, was used to analyze slope steepness, slope length and LS factor under different resolutions. Meanwhile, the changes of these parameters were calculated and analyzed in a none terraced area with the same resolution changes as comparison. The result showed that the DEMs which were accessed by UAV can express the terrace terrain features in details. Distribution of terraced terrain factors coincided with topographic features. These features showed high values distributed in the ridge area and small values distributed in terrace surface. With the decrease of DEM resolutions, the slope steepness of none terraced areas was decreased while the slope length was increased, and LS value was increased firstly and then decreased because of the fast decrease of the slope steepness, but the variation range was relatively small. For terraced areas, the portion of both small and large part of the slope steepness was decreased, average slope steepness was also decreased. Slope length had a clear increasing trend, so as the LS factor. Under the resolution of 20m, LS factor was overestimated for about 33%. Terracing is usually considered as a project factor in soil erosion models of soil and water conservation measures. Due to the large influence of resolution on LS factors, the estimation of erosion in terraced field needs to consider the effect of resolution changes.