The pressure propagation in high velocity compaction process is simulated based on the discrete element method in this paper. Because the full process is divided into elastic loading, plastic deformation and elastic unloading, the governing equations are established in three stages respectively. With the help of computing software PFC2D, the impacting force through different layers of powders can be obtained, which cannot be observed in experiment. The simulation results show obviously a delay phenomenon and serrate waves with different gradients in loading and unloading processes. Finally, the simulated low-level stress waves are compared with available experimental data, which are consistent with each other.