The invention discloses a mold pressing device for preparing a PVC blocky mold-pressed floor board. The mold pressing device comprises a fixed mold plate and a movable mold plate, and the fixed mold plate and the movable mold plate are oppositely arranged in the vertical direction. The lower portion of the fixed mold plate is connected with an upper mold block and cutters which are symmetrically distributed on the two sides of the upper mold block. First blades are arranged on the sides, close to the upper mold block, of the cutters, and the first blades are arc-shaped blades which are used for forming arc-shaped chamfers on one side of the floor board through cutting. The upper portion of the movable mold plate is connected with a lower mold block. A discharging block is arranged between the lower mold block and the upper mold block. When a board to be subjected to mold pressing is placed in the discharging block, the board is cut by the cutters to form the PVC blocky mold-pressed floor board while hot pressing is achieved through the upper mold block and the lower mold block. According to the mold pressing device, the cutters are additionally arranged on the two sides of the upper mold block, the side edge of the floor board is cut to form the chamfers in the hot pressing process, the internal structure of a floor board base material is prevented from being damaged, and the stability of the whole floor board is good; and the flatness of the cut surface is guaranteed through machining equipment, and the phenomenon that the surface of the floor board is uneven is avoided.