Compatibility tests are carried out on Ni-based Hastelloy alloys and stainless steel under the influence of the molten chloride salt NaCl-CaCl2-CeCl3 to investigate the corrosion behavior of molten salts with structural materials. Weight change measurements before and after the reaction tests show that the Hastelloy alloys have better corrosion resistance than stainless steel. The effects of molten salt purification on the corrosion behavior in the Hastelloy alloys are explored. The composition of the reacting phases is identified from transmission electron microscopy analysis and the corrosion mode is homogeneous corrosion with Cr and Fe diffusion, followed by Mo and Ni elution.