The invention discloses a motor shaft tool holder plate with a good stability. The motor shaft tool holder plate comprises a tool holder plate body, wherein sliding grooves are formed in the front surface of the tool holder plate body; mounting cutting tools are formed on the front surface of the tool holder plate body; a lower sliding block is movably connected with the front surface of the toolholder plate body; and a braking device is fixedly connected with the left side of the lower sliding block. The motor shaft tool holder plate with the good stability has the benefits as follows: the braking device, an upper sliding block and the lower sliding block are used cooperatively, the sliding grooves are formed in the top of the tool holder plate body, a wide-mouth groove is fixedly connected to the top of each of the left and right sides of each of the sliding grooves, so that the bottom of the lower sliding plate can slide into the sliding grooves through the wide-mouth grooves, thelower sliding block is enabled to slide, the protection on the lower sliding plate is controlled through the braking device, fixing bolts are distributed in the up-down direction from the center of gravity, the tool holder plate body can be thickened to 40 mm and prevented from being punched, and the stability of the tool holder plate body is improved.