Abstract: The fabrication of the Mg/Si alloy films using magnetron sputtering method is studied, in which a single compound cathode target is adopted. The structure of Mg/Si alloy films are measured and analysed by X ray diffraction, atomic force microscope, and transmission election microscope, respectively. For Mg/Si alloy films, amorphous silicon is scattered among Mg crystal, the orientation of Mg crystal is single on substrate.