Mg alloys are superior to other metallic biomaterials for temporary bio-application, owing to their biodegradability and biocompatibility features. However, the high reactivity and the rapid corrosion rate of Mg alloys are major barriers for their usage in bio-applications. In this paper, laser surface modification method is used to improve the surface properties of WE54. A 500 W pulse Nd: YAG laser beam is focused on the specimen through a 2 mm layer of simulated body fluid. As a result, a new microstructure and a Ca/P layer are obtained in a single process, which is conductive for the cell attachment.