In order to study the remaining velocity of projectile penetrating target to improve the precision of battle damage simulation, a series of simulation experiments of cylindrical projectile penetrating low-carbon target under various velocity of projectile, thickness of target and angle of attack were carried out by orthogonal experimental design method and LS-DYNA. The effect of each correlative factor was sorted by ANOVA of experimental condition parameters and result data. The THOR formula was modified by experimental data and the reciprocal equation was brought forth.