The invention relates to a technique for recovering sulfuric acid from sulfuric acid/sodium sulfate-containing wastewater by two-stage diffusion dialysis, two-stage electrodialysis and a bipolar membrane. The technique comprises the following steps: carrying out evaporative concentration on a raw solution, discharging the distillate, adding water into the concentrated solution for dilution, carrying out primary diffusion dialysis, directly recycling the received solution A as a dilute solution of concentrated sulfuric acid, adding water into the residual solution A for dilution, carrying out secondary diffusion dialysis, mixing the received solution B with the raw solution, adding caustic soda flakes into the residual solution B for neutralization to form a sodium sulfate mixed solution, refrigerating to crystallize, carrying out primary electrodialysis on the refrigerating solution for concentration, mixing the concentrated solution A with the solution formed by adding the caustic soda flakes into the residual solution B for neutralization, refrigerating the mixed solution to crystallize, carrying out secondary electrodialysis on the dilute solution A, returning the concentrated solution B to the refrigerating solution subjected to refrigerating for crystallization, and sending the dilute solution B to biochemical treatment. The diffusion dialysis treatment technique does not consume the electric energy, has low operating cost, and recovers the high-economic-benefit sulfuric acid in the waste solution.