The invention provides a method for secondary leaching of electrolytic manganese residue and manganese recovery. The method comprises the following steps of employing a reinforced approach of applying a direct-current electric field for ammonium manganous sulfate complex salt existing in the electrolytic manganese residue so that the previous manganese difficult to dissolve out in the ammonium manganous sulfate complex salt is leached out. Under the action of the electric field, manganese ions in a slurry are capable of migrating to a cathode region and dispersed quickly, and one part of the manganese ions are formed into attachments on a negative plate so that the concentration of the manganese ions in the slurry can be reduced, and the two processes are advantageous for leaching out manganese compounds including ammonium manganous sulfate. The method comprises the specific steps of preparing the electrolytic manganese residue with water and sulfuric acid into the slurry, activating and reinforcing under the action of the direct-current electric field, collecting the attachments on the negative plate, and performing solid-liquid separation on the rest slurry to obtain a leachate containing manganous sulfate, treating the leachate with ammonia water, adding sodium carbonate to the treated filtrate to obtain precipitate, and finally, mixing the precipitate with the collected attachments to obtain high-manganese content precipitate.