Abstract Hard body Armors are often deployed in ballistic applications to enhance resistance to Armor Piercing projectiles (AP). The main challenge for body armor designers is to find a best compromise between strength and weight to ensure a given level of protection. This paper investigates the effect of layer arrangement order, ceramic layer thickness, composite backing layer thickness and impact velocity on body armor performance using a numerical experimental design. In addition, the influence of bullet diameter on target damage and bullet erosion is examined. A finite element model (FEM) is evolved through Abaqus explicit software to simulate the ballistic impact of an ogival‐nosed projectile against body armor composed of a ceramic forward layer and a composite rear layer. The results revealed that the layout of the ceramic layer on the front side, that is, directly in contact with the projectile, and the composite layer on the rear side provides better ballistic performance than the opposite case. Furthermore, it is found that the thickness of ceramic and composite plates has a considerable impact on the ballistic performance of body armor. The ceramic thickness has a greater influence on the residual velocity than the composite one. Moreover, the full penetration and nonpenetration zones of the projectile have been highlighted according to the thicknesses of the ceramic and composite layers and using two impact velocities. Highlights Development of a numerical model simulating ballistic impact. Study the ceramic and composite thicknesses effect on ballistic performance. Analysis of target and projectile damage as a function of projectile diameter. Identification of full penetration and nonpenetration zones of the projectile.