When the peak stress of repeated impact is 1 /10 to 1 /6 and 1 /2 to 3 /4 of static yield stress of laser coating and base material, the Co2base、Ni2base coating and carbon steel、stainless steel base all have a repeated impact accu-mulative macroscop ical strain-hardening and softening phenomenon. The maximum deformation rate is up to 9. 4% , and the strain-hardening have a attenuation tendency from surface to inside. This phenomenon can only be found at a certain dep th. When coatingmicrohardness is below 500HV, hardening is the major phenomenon after the repeated mpact; when coatingmicrohardness is around 500HV, softening or hardening happened with the change of hardness, and cyclic softening and hardening may occur along with the increase of impact times. Low stress repeated macro-scop ical strain-hardening is a special characteristic ofmaterials under repeated impact load.