The properties and characteristics of DESs were introduced, the latest research progress about the eutectic solvents were reviewed, especially on the application of deep eutectic solvents (i.e. the choline chloride (ChCl)/urea mixture) in corrosion protection of Mg alloy, and the feasibility of surface treatment for magnesium alloys by deep eutectic solvents was analyzed. The preparation, corrosion resistance mechanism and the function of reaction medium of conversion coatings on magnesium alloys through the regulation of thermal field, acoustic field, electric field and DES membrane method were summarized and the deep eutectic solvent was combined with the hydrophobic biomimetic film at the same time to design a self-healing superhydrophobic coating on the surface of the magnesium alloy. The corrosion resistance of conversion films prepared by deep eutectic solvents was significantly higher than that of the magnesium alloy substrates, and the corrosion current density was significantly decreased. Finally, the future research orientation of corrosion protection of magnesium alloys was prospected. It is expected to have reference significance on the corrosion of magnesium alloys.