Abstract: Polymeric film was successfully prepared on the surface of a Mg-Mn-Ce alloy by the polymer plating. The contact angle of distilled water and thickness of polymeric film were determined by contact angle meter and spectroscopic ellipsometer. The chemical states of typical elements on film surface were characterized by X-ray photoelectron spectroscopy (XPS), and the film morphology was observed by atomic force microscopy (AFM). Tribological property of the film was evaluated on a nano scratch tester using loads of several tens to hundreds mN. The experimental results showed that the polymeric nano film was orderly formed on magnesium alloy surface. The conversion of functional performance from hydrophilic to hydrophobic was achieved as evident by the contact angle of distilled water (108.6 ° for the film and 45.8 ° for the substrate), and the friction coefficient was effectively reduced from 0.127 for substrate to 0.078 of hydrophobic nano film on the surface of polymer-plated magnesium alloy. Therefore, surface modification by polymer plating is considered as a promising technique in microelectromechanical system.