In this paper, the static corrosion experiment of 347H stainless steel alloyed with Cu and Mo elements was carried out in nitrate (60 % NaNO3+40 % KNO3) at 565 °C for 720 h. The effects of Cu and Mo elements on the corrosion resistance of 347H stainless steel in molten salt were studied by analyzing the phase composition, microstructure and chemical composition of the corrosion products. The results show that the grain refinement of Mo element makes the stainless steel have the best corrosion resistance of medium grain size. Furthermore, the formation of MoC contributes significantly to enhancing the intergranular corrosion resistance of the stainless steel. The stainless steel exhibited uniform corrosion in the nitrate solution. The corrosion layer displayed a dual-layer structure, with corrosion products of the protective matrix present in both the inner and outer layers. The outer layer comprised a mix of Fe oxide (Fe2O3, Fe3O4), NaFeO2, and a minor portion of MgFe2O4. Conversely, the inner layer primarily consisted of a spinel layer (FeCr2O4, MgCr2O4) and a thin Cu2O layer. The oxidation of Cu in the inner layer led to the development of a dense Cu2O layer, effectively impeding O2- plasma infiltration into the matrix.