Based on ANSYS/LS-DYNA code, the finite-element models were created to simulate the response of the aircraft panel structure impacted by high velocity projectile. The models proved to be effective through the comparison between the results of simulation and relative experiments. Then the impact process was simulated respectively considering the states of various types of stress in the panel. Through analyzing the simulation results, the influence of various stress states in the panel on impact response and damage mechanism was summed up. The conclusions indicated that the stress and particularly compression stress in aircraft panel structure can facilitate much more deformation and damage when the panel suffers high velocity impact.