PURPOSE: To ensure removal of nonmagnetic powder by forming magnetic fields in a powder transporting path, moving the magnetic powder by a change of the magnetic fields and simultaneously acting the external force exclusive of magnetic force, thereby removing the nonmagnetic powder.

CONSTITUTION: Magnetic toners 5 including extraneous materials receive the effect of the magnetic force of a magnetic force generating means 1 arranged on the outer side of a transporting pipe 3 of an extraneous material separating means, by which the magnetic toners are attracted to the inner walls of the transporting pipe 3. At this time, the magnetic toners 5 are magnetized and ear shapes are formed by a part of the magnetic toners as the magnetic toners 5 are attracted to each other by the magnetic force. At this time, the generating means 1 of magnetic force is drived in the opposite direction B with the transporting direction. As a result, the magnetic toners 5 are rotated in a direction D, by which the magnetic toners 5 are rolled and transported in a transporting direction (backward of B). The extraneous materials are separated by rotation of the magnetic toners 5 and are dropped and separated to the lower part of the transporting pipe 3 by their own weight.