<p>Provided is an electromagnetic clutch, in which a plurality of magnetic flux shielding slits extending in the axial direction and arcuately in the circumferential direction are formed individually in a rotor and an armature, and in which the magnetic flux by the excitation of a coil inserted on the anti-armature side of the rotor is passed from the non-slit portion of the rotor to the non-slit portion of the armature and from the non-slit portion of the armature to the non-slit portion of the rotor, so that a magnetic attraction is generated to push two frictional faces and so that the two frictional faces are separated by the demagnetization of the coil. The slits of at least one of the rotor and the armature are formed to change in such a taper shape that the side of the frictional faces may be smaller than the side of anti-frictional faces. Without inviting any drastic cost increase, the mutual pushing force of the frictional faces can be enhanced so that a higher torque transmission can be made even with the same size as that of the conventional structure.</p>
