Abstract: ZK60 magnesium alloys were treated by laser surface melting with different powers. The microstructure,roughness and corrosion resistance of the laser melted layer of magnesium alloy were studied. The results show that the laser melted layers with thickness of 100-200 μm are formed on the surface of magnesium alloy. The melted layer is mainly composed of fine equiaxed crystals and radial columnar crystals perpendicular to the interface of the melting layer, with a grain size of about 1.5 μm. The main phase composition of the melted layer is α-Mg phase and Mg Zn₂ phase. The surface roughness value and corrosion resistance of ZK60 magnesium alloy are improved by laser surface melting. When the laser power is 225 W, the melting layer is uniform and compact, and has a better appearance. Compared with untreated magnesium alloy, the corrosion potential of the melting layer with 225 W moves forward by about 0.114 V, the corrosion current density decreases by about 2 orders of magnitude, and the corrosion resistance reaches the best.