To provide a powder treating device capable of improving the treating efficiency of a material to be treated.

This powder treating device is provided with a cylindrical rotor 4, which has a receiving surface 7 vertically erected on the bottom 4b and the periphery of the bottom 4b and is driven and freely rotated around the rotary axis along the vertical direction, and an inner piece 5 attached on a supporting pestle hung from the upper side to the inside of the cylindrical rotor 4, disposed inside the cylindrical rotor 4 to be adjacent to the receiving surface 7 and acting on the material 1 to be treated with the rotation of the cylindrical rotor 4, and a deposition preventing means S for preventing the deposition of the material 1 to be treated is disposed at the center part of the bottom 4b.