NiAl bond coats with and without Hf addition (0.1 at%) were deposited on two types of superalloy substrates (i.e., DZ125L, no Hf, and DZ125, 0.51 at% Hf) using plasma spraying technique, and isothermally oxidized at 1150 ºC. It demonstrates that Hf addition in the bond coat is more effective than in the superalloy substrate for improving the bond coat oxidation resistance. In addition, though the substrate chemistry could affect the bond coat oxidation performance, this effect was very sensitive to the chemistry of the bond coat -obvious for the RE (reactive element)-free NiAl bond coat, but less obvious for the RE-containing bond coats (NiAlHf and NiCoCrAlY). Moreover, compared with the NiCoCrAlY bond coat, the NiAlHf bond coat showed significantly improved oxidation resistance, regardless of the substrate chemistry, suggesting that NiAlHf bond coat prepared by plasma spraying is a promising candidate for the thermal barrier coating application.