Abstract: An investigation of hypervelocity impact (HVI) has been performed by molecular dynamic (MD) method to study the high velocity penetration problem and the protection properties as well as the damage pattern of HVI on the spacecraft by the on-orbit debris. The numerical simulations of HVI by a Tungsten alloy projectile on a target were conducted by using EAM potential function. In addition, HVI on the penetrated hole on the target, the damage to the target, the generation of the debris cloud from the projectile size, the projectile velocity, the target thickness and the material models were explored qualitatively. It can be observed that the radial and axial distances of the debris cloud, the backward ejecta and the particle stack height become larger with the increase of the projectile diameter and the impact velocity. Moreover, the MD simulated results are compared with the high quality experimental results. The results indicate that the simulated debris cloud shape, backward ejecta and the particle stack height all fit well to the experimental results, verifying the effectiveness of the investigation using MD method.