A doping Nd:KGW femtosecond laser is used to ablate 0Cr18Ni9 stainless steel, and its ablation characteristics are studied. The surface profile of the ablated stainless steel and the associated effect in the ablation area are detected. Studies indicate that the ablation threshold of 0Cr18Ni9 stainless steel is 0.45 J/cm2; the ablation area successively appears grating structure, micro-convex structure, mastoid structure and concave structure, ablation hole along with the increase of the pulse number, and accompanied by heat affected zone,oxidation occurs at the ablation region; Microstructure in the ablation zone influences laser energy transfer and deposition further, local deep penetrating appears.