The disclosure discloses a method for preparing a battery-grade nickel-cobalt-manganese sulfate solution from low nickel matte. The method includes the following steps: grinding low nickel matte, then adding the ground low nickel matte to concentrated sulfuric acid, and carrying out atmospheric pressure leaching to obtain a first slag phase and a first liquid phase; carrying out evaporation concentration-cooling crystallization on the first liquid phase to obtain ferrous sulfate crystals; adding concentrated sulfuric acid to the first slag phase, and carrying out oxygen pressure leaching to obtain a second slag phase and a second liquid phase; adjusting pH of the second liquid phase to 3-4 to generate a precipitate, and removing the precipitate by filtration to obtain a filtrate; carrying out adsorption treatment on the filtrate by adopting chelating resin; washing the adsorbed chelating resin with a first sulfuric acid solution to obtain a washing solution containing Mg and Mn, and then washing the chelating resin with a second sulfuric acid solution to obtain a nickel-cobalt sulfate solution; and mixing the nickel-cobalt sulfate solution with the washing solution containing Mg and Mn to obtain the nickel-cobalt-manganese sulfate solution. According to the method of the disclosure, the battery-grade nickel-cobalt sulfate solution is prepared from the low nickel matte as a raw material, so that the recovery rate of nickel and cobalt is increased, and the acid consumption is reduced.