Abstract: Many application areas require complex 3D models. In order to ensure the uniformity and consistency of 3D models across different electronic devices but in many cases, 3D models must be simplified. In 3D terrains, textures, colors, regions, boundaries, and vertices are very important visual features. In order to preserve the visual characteristics of the 3D terrain, these visual features are introduced as constraint factors in the simplification process of 3D terrains.. Considering the texture color, region boundary and vertex importance, a new simplified scheme is proposed based on the quadric error metric to preserve these features during the simplification process. The improved simplification scheme is compared with traditional algorithm in an experiment. The results show that the improved simplification scheme can decrease geometric error while preserving visual features.