The objective of this study was to develop a method for the effective use of both pruned wood and porcelain stone scrap. Thus, we manufactured a wood-porcelain stone composite board, which has excellent waterproof property and incombustibility properties. In addition, we examined the conditions needed to manufacture the woodporcelain stone composite board as a construction material and evaluated the physical and mechanical properties of this board based on the Japanese Industrial Standard. The main results obtained were as follows: the wood-porcelain stone composite board made from pruned wood and porcelain stone scrap had excellent thickness swelling performance and the board had incombustibility properties that were better than commercial oriented strand board. In both single-layer and three-layer composite boards with weight ratios of porcelain stone particles of 40%, the internal bond strength exceeded the standard value of type 18 particleboard of JIS A 5908. However, the bending properties of the composite board were inferior to the type 18 particleboard standard. Therefore, it will be necessary to improve the bending properties of the board by changing the particle sizes of both the porcelain stone scrap and the pruned wood component.