The surface and cross-section damage morphology of fused silica glass elements under the action of nanosecond laser plasma shock waves was investigated. We use the finite element method to simulate the propagation law of shock wave inside fused silica glass, and analyze the damage formation mechanism based on the stress distribution law of shock wave inside glass. It is found that under the action of shock wave, the fused silica glass will be subjected to compressive stress along the wave front direction and tensile stress along the wave front direction. These two stresses cause arc-like layered fracture and radial fracture at the center of the laser irradiation. The superposition of the reflection of the shock wave causes the local tensile stress to increase, which caused damage to the rear surface. Through the finite element method, we intuitively analyzed the effect of plasma shock wave on optical components, and analyzed the damage mechanism of optical components under plasma shock waves.