Abstract: The discrete principle of the material point method (MPM) was briefly introduced, and a three-dimensional MPM code (MPM3D) was developed with the Johnson-Cook material model and Mie-Gruneisen equation of state to analyze the hypervelocity impact problems. The MPM avoids difficulty resulted from mesh distortion as in the Lagrangian method, and overtakes interface tracking and nonlinear convection term as in Eulerian scheme. The Taylor impact and orbital debris shielding problems are simulated by the MPM3D, and the calculated results are in agreement with the experimental results. The MPM is more efficient than the FEM in the analysis of hypervelocity impact problems.