The saturated vapor oxidation behaviors of GH2984 alloys at 750 °C were investigated by oxidation weight increasing method, X-ray diffraction and scanning electronic microscopy in different dissolved oxygen concentrations. The results showed that the oxide film of GH2984 alloys in different dissolved oxygen concentrations was of a single layer consisting of continuous Cr2O3 and disperse or local clustered internal oxidation products of Al2O3 and TiO2. The oxidation weight gain of GH2984 alloys slightly increased with increment of the dissolved oxygen concentrations in water vapor. Oxygenated treatment could accelerate the internal oxidation phenomenon, enhance the oxidation film thickness and make the scattered nodular bulges of Fe2O3 disappear and more Cr-rich nodular bulges form. Moreover, high dissolved oxygen concentrations did not affect the stabilization of Cr2O3 but decrease TiO2 content in the oxide film.