To provide a radial magnetic bearing of simple structure worked with a small number of current control power transistors.

A stator 30 is formed by laminating magnetic substances such as silicon steel plates in a thrust direction and arranging three electrode teeth 31, 32, 33 at equal spaces at the inner peripheral part. The electrode teeth 31, 32, 33 are respectively wound with coils 34, 35, 36. The coils 34, 35, 36 are connected by Y-connection and connected to a power transistor module 37 with six power transistors built therein. In the power transistor module 37, six built-in power transistors are controlled by switching of pulse width modulation or the like to control three-phase currents of U-phase, V-phase and W-phase.