For an exploration of the clean metallurgy method of low-temperature molten salt of galena concentrate, a research has been carried out on the reaction properties of the main gangue components SiO2, CaCO3, MgCO3, Al2O3 with Na2CO3 molten salt by using XRD analysis technique on the basis of thermodynamic analysis. The results show that SiO2 reacts with Na2CO3 to form Na2SiO3 at a temperature higher than 1 173 K; CaCO3 combines with Na2CO3 to form Na2Ca(CO3)2 at a temperature higher than 923 K and decomposes at a temperature higher than 1 123 K. MgCO3 decomposes into MgO at a temperature between 873~1 123 K, with no reaction with Na2CO3. At a temperature higher than 973 K, Al2O3 reacts with Na2CO3 to form sodium aluminate. In order to reduce the consumption of Na2CO3molten salt, the lead smelting temperature should be controlled at 1 073~1 173 K.