The influence of varying levels of impurity elements on the hot corrosion resistance of the DD98M alloy in Na₂SO₄+NaCl salt at 950 °C was investigated. The results indicate that the corrosion resistance of the DD98M alloy significantly decreases with an increase in impurity content, and the presence of nitrogen leads to an increase in alloy porosity. These porosities promote the rapid diffusion of molten salt and oxygen into the alloy, resulting in a bilateral diffusion of oxygen and sulfur, which leads to an accumulation of these elements at the oxide−matrix interface. This process contributes to the formation and propagation of interfacial cracks. A growth model was developed for hot corrosion products in alloys with varying impurity elements.