The invention discloses a manufacturing method of a sintered rare earth-iron-boron system permanent magnet with randomly distributed magnetic performance. The process route comprises the following steps: according to several different performance requirements of the magnet finally, designing several different proportion schemes, smelting respective raw materials into cast ingots respectively, and smashing the cast ingots to prepare micro powder; in the molding step, according to the final performance distribution requirement of the magnet, dividing a movable partition board for a molding mold cavity into different areas through calculation, filling magnetic powder with required performance is corresponding areas, then moving the movable partition board, and then carrying out conventional pressing flow paths such as orientation, pressing, demagnetization and demoulding. and then carrying out the steps such as sintering and tempering on green blanks. The magnetic performance can be randomly distributed on a magnetic pole face, so that the earth-iron-boron system permanent magnet material and technology meet various specific application requirements, the reduction of cost can be realized, and the magnetic performance requirement in specific fields are accurately met.