In This project we are discussing the dissipation of energy in stacking layers of bullet proof vest. We use the three fabrics (Kevlar, Nomex and Dyneema) for making the stacking of fiber then find the impact of the bullet on the stacking layer of fiber. For this purpose we find the momentum, and velocity of the bullet. We use the TexGen and ABAQUS software for modeling of fiber and the stress strain curve of the fiber