The invention provides a chromium-barium combined pollution soil treating method based on Na2SO3, belonging to the technical field of the environmental engineering. The chromium-barium combined pollution soil treating method based on Na2SO3 comprises the following steps of: mixing chromium-barium combined pollution soil and Na2SO3; while agitating the mixture by a closed side type rotary agitator, adding an acidic solution to adjust the pH value to be less than 8; and then preparing backfilled earth and backfilling the backfilled earth to the polluted field. In the invention, the Na2SO3 is used as the processing chemical only and can be used for synchronously processing the pollutants, such as Ba<2+>, Cr<6+>, BaCrO4 and the like, in the polluted soil , so that the harmless processing of the soil is realized.