An electromagnetic clutch includes a motor, a worm wheel rotatably driven by a motor, a rotor having an electromagnetic coil and rotatable about a same rotational axis as the worm wheel, an armature that is mounted to the worm wheel and is pulled into contact with the rotor upon application of electric power to the electromagnetic coil, so that the armature is rotated with the rotor, a cover member configured to cover the rotor and the armature, and a power supply mechanism disposed between the cover member and the rotor and connected to a power source for supplying power to the electromagnetic coil. The power supply mechanism includes a fixed frame body having a first power supply portion for receiving the power from the power source and fixed to the cover member, a rotary frame body having a second power supply portion in contact with the first power supply portion for supplying the power to the electromagnetic coil, the rotary frame body being fixed to the rotor and rotatably engaged with the fixed frame body; and a plate-like conducting member provided in the cover member, the conducting member coming into contact with a portion of the first power supply portion projecting from the fixed frame body.