Using the substrate of mild steel with thickness of 2 mm, Fe-Si-B amorphous ribbon with thickness of about 25 μm is cladded on substrate surface by pulse laser. The effects of pulse power P, pulse width W, pulse frequency F, beam diameter f of the pulse laser on the formation, the dilution rate, microstructure and microhardness of the coatings are investigated. The results show that the coating with well formation, the lowest dilution rate, lower pore density, and chemical bonding with substrate is obtained, when P=18.4 W, T=3.2 ms, F= 3.0 Hz, f=0.3 mm. With the increase of laser power, the crystallization in coating happens easily, and the contents and categories of crystallization phase of α-Fe, Fe₂B and Fe₃Si are increased, moreover, the thickness of coating increases while the microhardness of coating decreases. The highest microhardness in central coating is about 1400 HV , exceeding extensively that of mild steel with 100 HV.