The invention discloses a method for preparing a manganese sulfate solution with low manganous dithionate through desulfuration by using the slurry prepared by an anode liquid in electrolytic manganese production and manganese ore, and belongs to the field of electrolytic manganese production. According to method, the slurry prepared by the anode liquid and the manganese ore is used as a desulfurizing agent, meanwhile, a multi-stage spray washing tower with a sieve plate is additionally arranged for flue gas desulfurization and manganese immersion, after the obtained slurry is filtered, an oxidizing agent in the liquid phase is added to reduce the manganous dithionate in the slurry, so that the production of the electrolytic manganese and / or manganese sulfate is facilitate; the solid-phasesubstance obtained by filtering undergoes secondary acidolysis , and then the leaching rate of the manganese can be further improved; by adopting the process and the method, the leaching rate of themanganese can reach more than 94.3%, meanwhile, the high-concentration sulfur dioxide in the flue gas is reduced to the value lower than 100mg / m<3>, and the desulfurization efficiency can reach more than 99%; the prepared desulfurized manganese leaching solution is sent to an electrolysis section for electrolytic manganese production, the average single-shift yield is increased from 2.5kg-2.6kg inthe prior art to 3.1kg-3.2kg; and when the manganese sulfate solution which is prepared by the method and provided with the low manganous dithionate is used for electrolytic manganese production, theyield of the manganese can be improved, the plate loading rate of the manganese can be increased, the quality and the yield of the manganese can be improved, and the energy consumption and the production cost can be reduced.