Abstract: The accumulative effect of micro-scale plastic deformation of various frequencies can cause changes of surface microstructure and mechanical properties.Utilizing self-made machine to treat NiCrBSi laser cladding layer;OM to study geometric characteristic of plastic deformation and OM,SEM to observe influence of micro-forging on surface microstructure and cracking behavior of the laser cladding layer.It is shows that high frequency micro-forging can produce plastic deformation of about 150 microns depth onto the surface on NiCrBSi alloy clad and the dendritic crystallization microstucture which is peculiar of laser cladding layer,is broken into small pieces.Cracking suscep libility of laser cladding layer was improved greatly.