Abstract: It This paper builds up the geometry model of rod projectile penetration into metal target, then by means of supposing cracks propagation between the units, sets up the initial conditions of rod projectile, performs numerical simulations of extended finite element program based on Fortran penetration into metal target, and compares its results with the experimental data, then proves the accuracy and reliability of programs and the model. At last, it proceeds the simulation analysis of plastic modified, volume deformation and crack growth status of rod in the process of penetration.