To overcome the degradation of oxidation resistance caused by elemental interdiffusion between the NiAlHf coating and the nickel-based high-temperature alloy. A high-entropy coating of AlWCrNiMo was deposited as a diffusion barrier layer between the NiAlHf coating and the nickel-based high-temperature alloy N5 by magnetron sputtering, and static high-temperature oxidation experiments were carried out on the specimens after heat treatment. The diffusion barrier performance of the coating and the effect of the diffusion barrier layer on the antioxidant properties were evaluated by characterization means such as scanning electron microscopy, X-ray diffraction, and electron microprobe analysis. AlWCrNiMo had a single face-centered cubic crystal structure, which was dense and well-bonded with the N5 matrix and NiAlHf top layer. After oxidation at constant temperature of 1 100 ℃ for 25 h, a continuous γ?-Ni3Al-poor zone appeared in the specimen without a diffusion barrier (marked as NN), which was well suppressed by the diffusion barrier layer in the specimen with a diffusion barrier (marked as NAN). The width of IDZ (interdiffusion zone) and SRZ (secondary reaction zone) for the NAN specimen was 19.2 μm, which was significantly smaller than the 30 μm of the NN specimen. However, as the oxidation time increased, the barrier performance of the NAN specimen declined. After 50 h, the SRZ width of the NAN specimen was greater than that of the NN specimen; The diffusion barrier was gradually consumed and thinned out after 100 hours, and the area of the γ?-Ni3Al region of the NAN specimen was increased at this time; The diffusion barrier was reduced to 1.7 μm after 150 h, compared with 3.3 μm in the 25 h; And the diffusion barrier was completely disintegrated in 200 h, leading to its basic failure. The diffusion barrier was completely decomposed at 200 h, which led to its basic failure, and holes appeared at the interface of the diffusion barrier, and all the coatings were changed into the γ?-Ni3Al phase. The oxidized weight gain of NN and NAN specimens was much smaller than that of the uncoated specimens; The weight gain of the uncoated specimens after oxidation at 1 100 ℃ for 150 h was 1.91 mg/cm2, that of the NN specimens after oxidation at 1 100 ℃ for 150 h was 0.42 mg/cm2, while that of the NAN specimens was only 0.375 mg/cm2. After 200 h of oxidation, the weight gain of the NAN specimen and the NN specimen was basically the same:0.521 mg/cm2 and 0.527 mg/cm2. After isothermal oxidation at 1 100 ℃ for 25 h, the AlWCrNiMo high-entropy diffusion barrier significantly slowed down elemental diffusion. After 50 h of oxidation, the decomposed W and Mo elements in the high-entropy alloy promoted the precipitation of TCP phases. At the early stage of oxidation, the NAN specimen preferentially realized the transition from transient alumina to steady-state alumina, which provided good protection for the substrate, and its weight gain was significantly smaller than that of the single NN specimen. After 200 h of oxidation, the high-entropy diffusion barrier decomposed and failed, and holes appeared at the diffusion barrier interface, which was detrimental to the bonding of the coating.