Composite materials reinforced with nanofillers, have received particular attention in the defense and aerospace fields due to their superior strength-to weight ratio and energy absorption abilities. The present study investigates the effect of adding nanofillers (carbon nanotubes and graphene nanoplatelets) on the ballistic performance of body armor made of Kevlar composite materials. Therefore, a finite element model is developed using Abaqus explicit. The Hashin criterion is used to describe the behavior of composite materials. Residual velocity and target damage are analyzed for different percentages of nanofillers. It was found that there is a good agreement between the results of our numerical model and the results of the literature for different impact velocities. Moreover, it is revealed that the volume percentage of nanofillers has a considerable influence on the target damage but has a negligible effect on the residual velocity. The minimum target damage is observed for a nanofiller volume percentage of 0.5%.