Abstract: To meet the requirements of detail preservation in triangular model simplification,region segmentation principle of image is introduced,and a region segmentation method of mesh model is put forward based on region growth.A two-step adaptive method for simplifying triangle meshes based on multi-region paralleling is presented,which performs simplification proportionally over different regions,and makes the simplification much faster while preserving the details.A multi-region-paralleling-based implementation method of progressive mesh model is also proposed,which can obtain multi-resolution models that preserve the details effectively,and can realize the layer transition of those models.It is verified experimentally that this method can simplify triangle mesh model effectively,and has the characteristics of maintaining density distribution of triangle meshes.