Abstract: A rotary bevelment composite saw blade comprises an outside saw blade and an inside saw blade. The outside saw blade and the inside saw blade rotate around a coaxial center of rotation, the outside saw blade and the inside saw blade rotate in opposite directions, and the outside saw blade and the inside saw blade are arranged in parallel. A bearing is arranged between the outside saw blade and the inside saw blade. An inner race of the hearing positions the outside saw blade, and an outer race of the bearing positions the inside saw blade. The outside saw blade and the inside saw blade freely rotate along with the inner race and the outer race of the bearing, respectively. Friction, interference, and collision are not generated between saw blades of the rotary bevelment composite saw blade, and the rotary bevelment composite saw blade is efficient, stable, and reliable in a cutting process, and is suitable to cut materials such as metal, stone, wood, and glass.