The invention discloses a preparation method capable of increasing the electrochemical performance of a magnesium-sodium-doped lithium permanganate anode material. The preparation method includes the steps of firstly, dissolving manganese sulfate monohydrate into deionized water, and dropwise adding anhydrous ethanol; secondly, dissolving ammonium bicarbonate into deionized water; thirdly, mixing the obtained solutions, stirring, aging, performing precipitation and suction filtration, washing, and drying to obtain manganese carbonate; fourthly, pre-sintering the manganese carbonate, washing with hydrochloric acid, performing suction filtration, washing, and drying to obtain manganese dioxide; fifthly, grinding a lithium source, the manganese dioxide, a magnesium ion doping source and a sodium ion doping source, sintering, and cooling to obtain the magnesium-sodium-doped lithium permanganate anode material Li1-xNaxMgyMn2-yO4, wherein x=0.01-0.2, and y=0.01-0.2. The preparation method has the advantages that the method is simple in process, environmentally friendly, low in cost and capable of preparing the well-crystallized magnesium-sodium-doped lithium permanganate anode material even in distribution, and the electrochemical performance of the material is increased evidently.