Abstract: The mechanical characteristics of natural soils are significantly affected by their structure and original stress. As undisturbed soil and remolded soil possess different structural features, they demonstrate different mechanical properties in the case of minor stress. At present, lots of structural models have been established by remolded soil and experimental conditions without considering structure and original stress. Under the classical theories of elasto-plastic, based on soft clay in Guilin areas, combine with test indoor, according to the former model, an elasto-plastic constitutive model has been established to synchronously consider the structural characters and the original stress state based on the Modified Cam Clay. The comparison and analysis of various calculated results have shown the rationality and validity of the model. The applications of the model expressions make the strain result more correspond to the engineering practice. They have important significance for controlling not only rate of loading but also size of load grade during highway filled soil in Guilin areas.