The invention relates to a method for producing electrolytic metal manganese and application thereof. The method comprises the following steps of: leaching, namely adding electrolytic manganese anolyte into a combining tank, stirring, and testing and analyzing the content of Mn<2+> and H<+> in the electrolytic manganese anolyte; adding sulfuric acid, adding water quenching residue and a manganese dioxide ore, and introducing steam for heating in the feeding process; neutralizing, namely when the concentration of Fe<2+> in feed liquor is less than or equal to 0.001g/L, introducing ammonia water into the feed liquor for neutralizing; standing, namely performing pressure filtration on the feed liquor, adding into a standing pool, detecting the feed liquor, and determining that the feed liquor is qualified liquor when the concentration of manganese is 30 to 35g/L, the concentration of ammonium sulfate is 110 to 115g/L, the pH value is 6.0 to 7.0, sigma Fe is less than or equal to 0.001g/L and the concentration of Co, Ni and Zn is less than or equal to 0.001g/L in the feed liquor; and electrolyzing to obtain qualified electrolytic metal manganese. In the method for producing the electrolytic metal manganese, the water quenching residue is taken as a manganese source. The method has the advantages that: production cost is low; the mineral source for producing the electrolytic metal manganese is expanded; the leached feed liquor is not required to be purified, so that the production period can be shortened by 3 to 4 hours; and the total content of the manganese in leaching residue can be controlled to be below 3 percent.