Aiming at the problem that the sniper hits the target accurately through the glass, the trajectory of the sniper projectile penetrating the glass is simulated numerically. Taking the 7. 62 mm sniper bullet as the research object, the finite element model was established by using ANSYS/LS-DYNA software.The influence of attack angle and rotation speed on the deflection of bullet after penetrating glass under different incident angles was analyzed, and the influence law under different combinations was obtained. The simulation results show that the larger the incident angle is, the greater the deflection distance of the bullet after penetrating the glass is; when there is an attack angle, the longer the flying distance of the sniper bullet after penetrating the glass is, the greater the deflection distance is; the rotation speed has little effect on the deflection distance of the bullet after penetrating a barrier.