[Objective] Through studying three-dimensional(3D) modeling processe and method, we expected to provide solid basis for subsequent building of digital park. [Methods] Based on GPS mapping and ground survey of the park, visualization modeling was applied to the soil and water conservation project. [Results] Jiangxi Soil and Water Conservative Ecological Science and Technology Park was taken as an example, constrained triangulation and spatial interpolation were employed to solve some key issues. For example, seamless tiling of surface features and topography, soil body modeling, rapid generation of plant model, and so on. Finally a 3D model with aboveground and underground integration system including such elements as project measures, vegetation, and soil, etc., was constructed. [Conclusion] The developed 3D visualization system can make the water and soil conservative ecological demonstration park playing a better role in scientific support, social promotion, typical drive and demonstrative radiation.