In the presents work, the effects of the surface oxidation of the Ni50Zr25Nb25 metallic glass on the corrosion behavior in nitric acid environment were investigated. The oxidation kinetics at 200 and 400 °C in air environment followed two-stage rate law. SEM and XPS investigation revealed the surface of thin (106 nm) amorphous oxide film composed of NiO, Ni2O3, ZrO2, and Nb2O5 when sample was oxidized at 200 °C. However, oxidation at 400 °C resulted in a thicker (721 nm) amorphous oxide film, enriched with only ZrO2 and Nb2O5. Potentiodynamic polarization results of the thermally oxidized metallic glass at 400 °C exhibited the wider passive range and significantly higher corrosion resistance in concentrated nitric acid when compared to the as-prepared and oxidized sample at 200 °C. After polarization at 2.2 V (Vs. Ag/AgCl), thermally oxidized sample at 400 °C exhibits smooth surface while the as-prepared MG undergoes a severe dissolution in 11.5 M nitric acid.