A corrosion-resistant and high-performance sintered neodymium-iron-boron magnet, a preparation method therefor, and a use thereof are provided. The sintered neodymium-iron-boron magnet is prepared by pulverizing, forming, and sintering. The sintered neodymium-iron-boron magnet contains: 28.5 wt % to 32.5 wt % of R; 0.88 wt % to 0.94 wt % of B; 0.1 wt % to 0.3 wt % of Ga; 1.0 wt % to 3.0 wt % of Co; and 400 ppm to 1000 ppm of O. The sintered neodymium-iron-boron magnet capable of inhibiting reduction of coercive force and improving the coercive force can be obtained by means of an oxygen adding operation, and meanwhile, the corrosion resistance of the magnet can be improved.