Surface crack of steel components was repaired with two bundle of laser. There was an obvious joined band between filled region and substrate of component. The microstructures of repaired region were adnate cellular crystal, dendrite crystal, and needleshaped crystal. The phases of dendrite crystal in repaired region were consisted of γ Ni which contained plenty of Cu, Fe. The phases in the gaps among dendrite crystals wereγ Ni, NiSi 2, Cr 3Ni 2, CrSi. The hardness of filled layer in repaired region were HV 0.2 400～HV 0.2 450, then the hardness values decreased from the surface to transition region.