As the unknown nature of mechanism of projectile penetrating the concrete target and the complexity of the mechanical properties of concrete,the projectile penetration concrete can be seen as a gray process.The establishment of methods and processes about the gray simulation and prediction model GM(1,n)were described.Through the gray model GM(1,n),the simulation and prediction of penetration depth of projectile penetrating the concrete target can be achieved.The calculation results show that the model simul...