Abstract: An implicit material point method(MPM) is presented in this paper to simulate long run-out landslide. The generalized interpolation material point method(GIMP) is used to calculate the run-out of landslide with MUSL scheme. The elastoplastic model based on the Drucker-Prager yield criterion is adopted in this paper. Firstly, the effectiveness of the material point method to simulate the large deformation problem is verified by the experiment test. Secondly, the GIMP is used to simulate the failure process of the landslide, and the influence of internal friction angle on the slipping distance of the large deformation landslide is discussed. The results show that the internal friction angle plays a decisive role in the slipping distance of the landslide. The smaller of soil internal friction angle is,the longer of the slipping distance become. For unsaturated soil strength parameters by UU shear test, the internal friction angle is small because of the soil consolidation and drainage is poor. It is important to ensure that the soil is fully consolidated and drained for the landfills, otherwise it is easy to become long run-out landslide.