The invention belongs to the field of plate machining, and particularly discloses a plate engraving machine fixing device. The plate engraving machine fixing device comprises a workbench, side platesare symmetrically and fixedly connected to the two sides, in the length direction of the workbench, of the top side of the workbench, and sliding grooves are symmetrically formed in the portions, located between the two side plates, of the top side of the workbench; movable plates are symmetrically and slidably installed between the two sliding grooves, and driving mechanisms are connected to thesides, far away from each other, of the two movable plates; and clamping grooves are symmetrically formed in the sides, close to each other and located between the two sliding grooves, of the two sideplates, clamping blocks are slidably installed in the clamping grooves, and first springs are installed on the sides, close to each other, of the two clamping blocks in the two clamping grooves. According to the plate engraving machine fixing device, through the structural design of the movable plates, the clamping grooves, the clamping blocks, the first springs, supporting rods, connecting rods,clamping plates, connecting blocks, second springs, fixing rods and pushing rod motors, the top side edge of a plate can be extruded and fixed while the side wall of the plate is extruded and fixed.