In this article, the discrete element method is used to research the force distribution of two-dimensional granular system under the condition of isotropic compression and pure shear. The simulation results are compared with the experimental results under the same conditions. Then we simulate the force distribution of two-dimensional granular system with point defects under the condition of isotropic compression and pure shear and compare the results with the results without point defects. The affects of point defects to granular system are found.