PURPOSE: To provide a polar electromagnet device which reduces power consumption and moreover improves certainty of reset operation.

CONSTITUTION: A small diameter part 4b having a prescribed length is provided on the other end part 4b of a plunger 4 which is arranged inside a coil in the state allowing reciprocating motion and whose one end part is opposite to coupling piece of a yoke 2 and the other part 4b is projected from the tips of both side pieces of the yoke, and an engaging part engaging loose with the small diameter part on a base end of a reset member 8 whose base end 8a is linked with a plunger in order to transmit the external force to the plunger at the time of receiving the external force for returning the plunger to a position to be attracted by the coupling piece. Then, this reset member 8 is supported by the other end part 4b of the plunger 4 so as to allow shifting by a prescribed amount in the direction of a reciprocal movement of the plunger 4.