PURPOSE: To provide enough adhesive strength via application of simple constitution, and prevent occurrence of a wrinkle on a kneading board even at the time of exposure to a strong force by spreading a hot melt adhesive layer on the top side and one of right and left sides of a box type kneading board polymer formed out of a plurality of stacked rectangular waterresistant kneading boards.

CONSTITUTION: A dental cement kneading board set 1 is formed out of stacked rectangular waterproof kneading boards 2 of synthetic paper mainly composed of polypropylene. Also, sponge type back sheets 3 of polyurethane having the same size as the boards 2 are attached to the bottom of the set 1, thereby forming a box type kneading board polymer 10, and a hot melt adhesive mainly composed of a rosin is, for example, applied to the top side 7 and the right side 9 of the polymer 10 via a roller. Then, the adhesive is cooled and solidified at ordinary temperature to spread adhesive layers 6 and 7. As a result, enough adhesive strength can be provided, and the boards 2 are not displaced from each other to such an extent as forming a wrinkle, even when a strong force acts in any direction on the uppermost surface thereof, due to dental cement strongly kneaded thereon by the use of a knife.