Abstract: In order to estimate the anti-penetrating power of reactive power steel fiber concrete, the deformation and failure model of media is presented according to the relation between state of media and energy distribution in the process of penetration of projectile,and the the scaling relation between near the penetration cavity that energy dissipated and crushing zone is uncovered. Deformation of the medium near the cavity is considered as one-dimension deformation state and similar to hydrokinetics state, accordingly the formulae on of wider applicable confines for calculating penetration is deduced and simplified. And it is considered that the penetration depth is determined by the mass, figure, velocity of the projectile and the strength, density, rupturing temper, deformation wave velocity of the target. The reliability of the formulae is proved by repeated test, and a conclusion is gained that the anti-penetrating ability of RPC is three times as that of general concrete.