Abstract: The surfaces of 0Cr15Ni5Cu2Ti steel were modified with TiAlSiN coating deposited by TiAlSiN coatings.The influence of the microstructures and phase structures of the TiAlSiN coating on the high temperature oxidation resistance and interfacial adhesion was investigated with X-ray diffraction,scanning electron microscope,energy dispersive spectroscope and micro-hardness tester.The preliminary results show that when it comes to property modification,the TiAlSiN coating makes the difference.To be specific,the fairly uniform,compact TiAlSiN coating,with randomly distributed micro-pores and large “droplets”,increased the average micro-hardness to 1971.4 HV_0.2,significantly decreased the oxidation rate,and considerably enhanced the high-temperature oxidation-resistance.Much research remains to be done to increase the rather low interfacial adhesion(with a binding force of ~10 N).