A high hydrophobic Ni-Cu-SiC coating with a graded nanostructure was successfully deposited on the Mg-Li alloy via electroplating and stearic acid modification. After stearic acid modification, the as-prepared Ni-Cu-SiC coating displays high hydrophobicity with contact angle of 156.0°. Furthermore, surface wettability transition from high hydrophobicity to superhydrophilicity can be achieved via UV–vis irradiation, and subsequently, the high hydrophobicity can recover to hydrophobicity via stearic acid re-modification. This work could provide a novel way to fabricate functional surface on Mg-Li alloy and wider industrial application for Mg-Li alloy.