To provide an electromagnetic coupling device providing a rust preventing effect without causing a decrease in operational stability.

This electromagnetic coupling device X includes: an electromagnet portion 1 provided with a metallic yoke 11 and an exiting coil 12 in the yoke 11; an armature 2 forming a magnetic circuit together with the electromagnet portion 1; and a plate 4 arranged in a position opposed to the armature 2, and is so configured that with the exiting coil 12 exited, the armature 2 is moved in the axial direction of a shaft S against the pressing force of a pressing member 3 and pressed to the electromagnet portion 1. In the electromagnetic coupling device X, at least the contact surfaces (yoke contact surface 11A, armature contact surface 2A) brought into contact with each other under an exiting condition, of the yoke 11 and armature 2 as metallic components allowing the magnetic circuit to internally pass through under an exiting condition, are rustproof-treated by organic resin.