The invention relates to a processing method for high-quality bamboo flattened floor. The processing method comprises the steps of selecting materials and splitting, pre-forming concave slots, cooking and softening, flattening at a high temperature, drying, processing comb teeth, preparing substrate, gluing, transversely reinforcing and the like. The bamboo floor has density which is only 0.6g/cm<3> (optimum density of produced floor), has surface-layer density and core-layer density which are in step distribution, has relatively good elasticity and keeps natural textures of a high-hardness bamboo green surface. Besides, the high-quality bamboo flattened floor can be mounted in a staggered mode on the scene, and floor units are mutually clamped, so that the floor has higher integral stability. The high-quality bamboo flattened floor has the advantages of being not liable to crack, high in surface hardness and good in wear resistance, simple in process, and the like, and is novel high=quality floor with excellent physical property and excellent mechanical property.