A method for purifying a nickel cobalt manganese leaching solution, comprising the following steps: heating a nickel cobalt manganese leaching solution, stirring, adding a manganese powder, adjusting pH to acidity, performing a reaction, and filtering, to obtain an iron-aluminum slag and an iron and aluminum-removed liquid; heating the iron and aluminum-removed liquid, stirring, adding a manganese powder, adjusting pH to acidity, performing a reaction, and filtering, to obtain a copper slag and a copper-removed solution; heating the copper-removed solution, stirring, adding an alkaline solution, adjusting pH to alkalinity, performing a reaction, and filtering, to obtain a nickel and cobalt-precipitated solution and nickel cobalt manganese hydroxide; and adding water and slurrying the nickel cobalt manganese hydroxide, heating, adding an acid solution to dissolve, adjusting pH to acidity, performing a reaction, heating, then adding a manganese powder, adjusting pH to acidity, and filtering, to obtain an iron-aluminum slag and an accepted nickel cobalt manganese sulfate liquid; wherein, in step, the manganese powder is a manganese oxide ore powder and a manganese carbonate ore powder; in step, and step, the manganese powder is an elemental manganese powder; in step, the adjusting pH to acidity is adjusting pH to 4.0-4.5; in step, the adjusting pH to acidity is adjusting pH to 5.5-6.5; in step, the adjusting pH to alkalinity is adjusting pH to 7.6-8.5; and in step, the adjusting pH to acidity is adjusting pH to 5.0-5.5; and in step, the iron-aluminum slag is returned to step to react with the nickel cobalt manganese leaching solution; wherein, a main component of manganese oxide ore is MnO 2, and a main component of manganese carbonate ore is MnCO 3. heating a nickel cobalt manganese leaching solution, stirring, adding a manganese powder, adjusting pH to acidity, performing a reaction, and filtering, to obtain an iron-aluminum slag and an iron and aluminum-removed liquid; heating the iron and aluminum-removed liquid, stirring, adding a manganese powder, adjusting pH to acidity, performing a reaction, and filtering, to obtain a copper slag and a copper-removed solution; heating the copper-removed solution, stirring, adding an alkaline solution, adjusting pH to alkalinity, performing a reaction, and filtering, to obtain a nickel and cobalt-precipitated solution and nickel cobalt manganese hydroxide; and adding water and slurrying the nickel cobalt manganese hydroxide, heating, adding an acid solution to dissolve, adjusting pH to acidity, performing a reaction, heating, then adding a manganese powder, adjusting pH to acidity, and filtering, to obtain an iron-aluminum slag and an accepted nickel cobalt manganese sulfate liquid; wherein, in step, the manganese powder is a manganese oxide ore powder and a manganese carbonate ore powder; in step, and step, the manganese powder is an elemental manganese powder; in step, the adjusting pH to acidity is adjusting pH to 4.0-4.5; in step, the adjusting pH to acidity is adjusting pH to 5.5-6.5; in step, the adjusting pH to alkalinity is adjusting pH to 7.6-8.5; and in step, the adjusting pH to acidity is adjusting pH to 5.0-5.5; and in step, the iron-aluminum slag is returned to step to react with the nickel cobalt manganese leaching solution;