In order to improve the corrosion resistance of magnesium alloy, 2D-MoS2 thin films were prepared on magnesium alloy surface by electrophoresis deposition. The electrophoresis solution was prepared by dispersing MoS2 powder into deionized water by means of Triton X-100 (electrophoresis grade). The experiment mainly explored the influence of different electrophoretic deposition time on the corrosion resistance of the thin films. The corrosion resistance and wettability of 2D-MoS2 films were evaluated by dynamic potential polarization curve test and hydrophobic performance test, respectively. The microstructure and phase structure of 2D-MoS2 films were characterized by scanning electron microscope (SEM) and X-ray diffractive (XRD). The micromorphology of thin films and their protective effects on magnesium alloys when electrophoretic deposition time is 30, 60, 90 and 120 s were analyzed. The results show that MoS2 film are the most complete and compact when electrophoretic deposition time is 60 s. With the increase of deposition time, the film thickness increases and obvious cracks appear. When electrophoretic deposition time is 60 s the most positire corrosion potential of this surface-treated magnesium alloy is –0.99 V, which is positively shifted by 0.46 V compared to that of untreated magnesium alloy. And minimum corrosion current density is 9.78×10–6 A.cm–2, which decreased by 93%. After electrophoresis, the static contact angle of the metal increases and reaches up to 86.34°. The conclusion is that 2D-MoS2 thin films prepared on the surface of magnesium alloy can effectively improve the corrosion resistance of magnesium alloy, and the corrosion potential of films is the most positive and the corrosion current density is smallest when the deposition time of MoS2 films is 60 s, which shows the best corrosion-resistant performance.