Abstract: Foreland basins form by lithospheric flexure under orogenic loading and are filled by surface transport of sediment. In order better to understand the mechanism of the evolution of foreland basin which is subjected to various loads applied at its literal boundaries, we carried out a three dimensional flexural and sedimentary model after study of the mathematical geology process of foreland basin, and test an synthetic model, which shows a perfect result of the thrusting process and the pattern of foreland basin in response of the lithospheric flexural subsidence, and then we model the erosion and sediment which is the result of the drainage system on the basis of the dynamic topography. The modelling also indicates the interplay and limitation between the thrust stacking, elastic flexural subsidence and sediment transport. The 3-D model brings us not only a theoretical basement but also a useful tool for the deep study of foreland basin.