Abstract: Al CoCrFeNiCu high-entropy alloy coatings were prepared on the surface of 35CrMo steel by plasma cladding,and the coating samples were annealed at different temperatures. The microstructure and phase structure of the coatings were characterized by metallographic microscope and X-ray diffractometer, and the microhardness and corrosion resistance of the coatings were tested by microhardness meter and electrochemical workstation, respectively. The results show that the coatings are mainly composed of dendrites, and the grain size increases with the increase of annealing temperature. The coatings are simple phase structure of FCC and BCC, and the new Fe-Cr phase with BCC structure is precipitated by annealing treatment.The hardness and corrosion resistance of the coatings are obviously better than that of the substrate. The hardness of the coatings increases first and then decreases with the increase of annealing temperature. The average value of the microhardness of the coatings is the highest when the annealing temperature is 800 ℃, reaching 422.4 HV10. The corrosion resistance of the coating increases with the the increase of annealing temperature, and the coating has the best corrosion resistance under the annealing condition of 900 ℃.