The invention discloses a modifying method of a ternary anode material. The modifying method is characterized by comprising the following steps: (1), adding the ternary anode material LiNixCoyMnzO2 into an acetic acid solution, stirring for 20 min-40 min, and then washing and drying, wherein x is not less than 0.3 and not more than 1, y is not less than 0 and not more than 0.5, z is not less than 0 and not more than 0.5, and (x+y+z) is equal to 1; (2), adding a lanthanum element into the dried ternary anode material, wherein the lanthanum element is metal lanthanum or a compound of metal lanthanum of which the mass is 0.5%-2% of the mass of the ternary anode material; then adding distilled water, uniformly stirring to form slurry; and (3), directly heating the slurry material in an air atmosphere to 600-900 DEG C according to a heating rate step by step, sintering for 2-8 hours, cooling to the room temperature, grinding and sieving to obtain the lanthanum oxide-coated ternary anode material.