Disclosed are a reaction tower, a production system, and a production method for producing potassium manganate. The reaction tower includes a reaction tower body and a bubble generator. The reaction tower body has a reaction chamber. The bubble generator includes an outer housing. The outer housing is disposed in the reaction chamber and has a gas flow channel therein. The outer housing is configured to direct an external reactant gas into the gas flow channel. The outer housing is provided with multiple first pores each having a diameter less than 10 mm, via which the gas flow channel communicates with the reaction chamber. The reaction tower is used in the production system. The reactant gas is introduced into the reaction chamber in the form of small bubbles by the action of the bubble generator, to increase the area of contact of the reactant gas with manganese ore powder and lye.