The corrosion behavior of the alloy NF616 covered with a film of molten 0.55ZnCl 2 -0.45KCl (mole fraction), similar to that found in waste incineration plants, was examined in air at 673 K by the electrochemicalimpedance spectroscopy (EIS) technique. For comparison, the corrosion of the same material immersed in the deep salt was also studied. The electrochemical impedance spectra for the corrosion of NF616 beneath a film of fused salt consisted of a semi-circle at high-frequency port and a line at low-frequency port indicating a diffusion-controlled reaction. Contrary to the corrosion beneath salt film, the corrosion of the alloy in deep molten salt presented the characteristics of two capacitive loops during all the duration of the experimental test. This different EIS features under two corrosion conditions may be related to the different supply of oxygen amount. In this paper, suitable equivalent circuits representing the corrosion of the alloy under the two different corrosion conditions are proposed to fit the corresponding impedance spectra and electrochemical parameters in the equivalent circuits are also calculated.