To introduce a mixture to be processed, in which powder and granular material with relatively large specific gravity and hardness and accompanying lightweight foreign substances are mixed together, inside a system and separate the same by a dry method.Disclosed is a powder and granular material separation processing device X that is connected to an external suction machine such as a dust collection device and an electric vacuum cleaner, introduces by suction a mixture to be processed into a separation processing container 1, and discharges lightweight foreign substances to the outside of a system while collecting powder and granular material inside the system. The separation processing container 1 has a suction introduction tube 2 that is attached and sealed as the upper part structure of a hopper tank 4 that collects and stores the powder and granular material and receives the mixture to be processed on the circumferential surface thereof, and a suction discharge tube 3 that is connected to an external suction machine on the upper surface thereof. In addition, the separation processing container 1 has a separation cone 11 with a funnel-shaped bottom surface and a cylindrical opening 13 that hangs in a protruding shape downward from the tip part of the separation cone 11 and of which the opening diameter thereof is reduced stepwise to have multiple steps. The suction discharge tube 3 has a multiple tube configuration at the tip part thereof in which each tube is given a small diameter corresponding to each opening diameter of the cylindrical opening 13 to be loosely inserted and face the tip part of an opening.