libri" size="3">Soil structure is the main reason causing the differences between natural and remolded soils. The soil structure have impacts on methods and means of geoteehnical engineering. This paper establishes a structural consti- tutive model of Haikou red clay. Based on structural quantitative indicators, the concept of comprehensive structure potential is introduced. It builds quantitative expression among geoteehnical microstructure, cementation and macro- scopic mechanical effects. The stress typical structural parameter and strain typical structural parameter are defined. They are obtained through the isotropic consolidation test and p = constant shearing test respectively. Both,~parameters exist the normalized linearization relationship relative to average principal stress. The result can describe the Haikou undisturbed red clay structure. These parameters are used to modify the K-G model. A numerical simulation is car- fled out. Results showed that the modified K-G model can describe the structure of Haikou undisturbed red clay, and well predict the stress-strain relationship of undisturbed red soil.