Abstract: AZ91D magnesium alloy substrate surface was treated by high energy shot peening (HESP) for different times (0, 20,30,40 min), and then aluminium film was plated on the HESP substrate surface by magnetron sputtering technique. The microstructure and corrosion resistance of the aluminium film were studied. The results show that the surface structure of the aluminium film on the HESP substrate surface was uniform and dense, and the film was relatively thick; with increasing HESP time, the structure was finer and more uniform, and the film was thicker. After HESP for 40 min, there was a significant transition layer between aluminium film and substrate, and the bonding force was 16 N, which was 3.2 times that without HESP. Compared with those without HESP, the free corrosion current density of the aluminium film on the HESP substrate surface in NaCl solution and the etch pit depth formed in salt spray for 24 h were relatively small. With increasing HESP time, the free corrosion current density and the etch pit depth both decreased, indicating that the electrochemical and salt spray corrosion resistance of the aluminium film were significantly improved.