To efficiently enhance magnetic separation by alternately arranging a series of magnetic discs and nonmagnetic discs between electrode members and to generate a necessary magnetic field gradient by a series of discs and to reduce the loss of magnetic field intensity caused by fringing.

A generator having a pair of opposed electrodes generates a magnetic field 20 in the gap 24 between the both electrodes. The flexible belt 30 moving along a route moves around the gap and sends a weak magnetic material and a nonmagnetic material to the route. The force of an air source is turned toward the interior of the curved part between the upper and lower parts of the belts to separate the curved part of the belt from the gap 24.