A fire-proof wood board with tenon engagement comprises: a surface plate made by hard, fire-proof, water-proof, and wear-endurance wood textured plate; a fire-proof liner plate below the surface plate; and a substrate below the fire-proof liner plate and each end of the substrate being formed with a notch and a tenon; the tenon having a configuration corresponding to the notch so that the tenon and notch being engaged to connect two adjacent substrates together. The fire-proof liner plate is made of material selected from one of calcium silicic acid plate, magnesium oxide plates, cement plates, and gypsum plates. The substrate is selective from one of wood splint plates, wood compressing plates, decorative higher pressure plates. Furthermore, the fire-proof wood board is used as one of floorboards, wallboards and ceiling boards.