PURPOSE: To provide an electromagnet exciting device which suppresses a circuit power consumption.

CONSTITUTION: An electromagnet exciting coil 3 is connected to a power supply 1. A field effect transistor FET connected to the negative electrode of the coil 3 is chopper-controlled by a pulse generating circuit 4. A regenerative circuit composed of a regenerative diode D1 and a regenerative transistor Q1 connected in series is connected to the coil 3. A first drive transistor Q2 and a second drive transistor Q3 are connected to the base of the regenerative transistor Q1, and the first drive transistor Q2 is connected to the an input signal generating circuit 5. The first drive transistor Q2 is kept ON by an input signal for a certain time just after a switch 2 is turned ON. Therefore, the base current of the regenerative transistor Q1 is kept comparatively large for a certain time and then becomes small when the first drive transistor Q2 is turned OFF after a certain time elapses.