To provide an electromagnetic switch capable of improving an anti vibration shock performance without increasing an energizing force for resetting.

The electromagnetic switch comprises: a contact device 1 which has a pair of fixed contacts 4a, 4b fixed in an arc-extinguishing chamber container 3 with a predetermined gap therebetween, and a movable contact 5 arranged to be attachable to or detachable from the pair of fixed contacts; and an electromagnet device 2 having a movable plunger 13 movable between an opening position for separating the movable contact 5 from the fixed contact and a closing position for pressing the movable contact 5 in contact with the fixed contact. The arch-extinguishing chamber container 3 is provided with permanent magnets 16a, 16b for arc-extinguishing an arc generated in pole opening, during which the movable contact is separated from the fixed contact from a condition that the movable contact is in contact with the fixed contact. A magnetic circuit La is formed, which is returned to the permanent magnet via the movable plunger from the permanent magnet while the movable plunger 13 is at the opening position.