Abstract: In order to analyse the effect of gradient distribution on the performances of graded-impedance materials against hypervelocity impact, experiments and numerical simulations with titanium alloy as the impact face (front impact) and magnesium alloy as the impact face (back impact) were designed and carried out for the graded-impedance materials with graded-impedance distribution of titanium alloy/aluminium alloy/magnesium alloy. The characteristics of debris cloud and rear wall damage were obtained. The impact pressure and internal energy conversion characteristics of projectiles and targets under different conditions were analyzed. The results show that front impact is beneficial to increase the impact pressure, promote the transformation of kinetic energy to internal energy, and thus improve the protection ability.