Inconel 625 powder was cladded by semiconductor laser with varying single process parameter,the effect of laser power,scanning speed on the cladding morphology,macroscopic size and dilution rate was studied. The formation process parameter range of the deposited layer with low dilution rate,good metallurgical bonding,no cracks,and no pore defects was obtained. The cladding microstructures and mechanical properties were also analyzed. The results show that the surface hardness of the cladding layer is gradually increased from the bonding surface to the top of the cladding layer,the microstructure of the cladding layer represents flat crystal,coarse dendrites and fine dendrites. The main phase of the cladding layer is γ-Ni. Acid corrosion tests with high temperature naphthenic show that Inconel 625 cladding layer has better corrosion resistance than traditional materials（316L,304,20 # steel）.