Laser shocking peening is a widely applied surface treatment technique that can effectively improve the fatigue properties of metal parts.We observe many micro-scale arc plastic steps on the surface of Zr47.9 Ti0.3Ni3.1 Cu39.3Al9.4 metallic glass subjected to the ultra-high pressure and strain rate induced by laser shock peening.The scanning electronic microscopy and atomic force microscopy show that the arc plastic step (APS) has an arc boundary,50-300 nm step height,5-50 μm radius and no preferable direction.These APSs have the ability to accommodate plastic deformation in the same way as shear band.This may indicate a new mechanism to accommodate the plastic deformation in amorphous metallic glass under high pressure,ultra-high strain rates,and short duration.