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The corrosion behaviors and mechanism of Ni-14%Cr alloys in molten salt with Na_2SO_4 at 1000℃ was investigated by means of XRD analysis and SEM observation. Results show that the alloys were subjected to the accelerated corrosion in molten salt and the corrosion kinetic of the alloy obeys the parabolic law. On the other hand, the corrosion-resistance of the alloy could be improved significantly by increasing of chromium content. Corrosion products may be divided into three layers, i. e. NiCr_2O_4, CoCr_2O_4, CoNi2S4, AlWO_3 and Al_2O_3 granule are included in the outside of the scales, the continuous Al_2O_3 layer is localed in intermediate layer, and the sulfides is in the internal layer. The Cr_2S_3 phase in Ni-14Cr prevents the S and O from the matrix of the alloy. The morphology examinations tend to support the sulphidization-basic dissolution model previously proposed for hot corrosion mechanism.