Abstract: It has become a trend of the industry to apply the 3D digital model for aided design, effect display, construction guidance and later stage management of landscape architecture. Plants are key elements of landscape architecture. By discussing the necessity of building and applying three-dimensional digital model of landscape plants, basing on Koelreuteria paniculata as an example, using PlantFactory, a 3D Plant modeling software, to build a 3D model. On this basis, the authors constructed a small three-dimensional digital model library containing 15 typical garden tree species. Finally, this paper explores its applicability and effectiveness through the application of the 3D digital model of garden plants in the three aspects of plant morphological cognition, plant landscape design and construction of landscape information model (LIM).