The invention discloses a method for preparing a nitride-reinforced high-entropy alloy coating through thermal spraying. Plasma spraying equipment is adopted to spray mixed powder composed of Al powder, Fe-Cr-B-Si, Mn powder and Ni-Cr-B-Si in a certain proportion on the surface of the low-carbon steel, in the spraying process, the active elements such as Cr and Al react with the activated N to form a nitride, wherein the nitride is fine and dispersed, and then deposits on the surface of the carbon steel to prepare the nitride-reinforced AlCrFeMnNi high-entropy alloy coating, and the coating has the advantages of being basically dense, small in porosity and high in wear resistance.