A wireless charging system includes a first winding portion, a second winding portion which is disposed with an interval between the first winding portion and the second winding portion in an axis direction of the first winding portion, and a pair of magnetic members which are disposed so as to sandwich the first winding portion and the second winding portion in the axis direction. In this case, protrusion portions which protrude toward the other magnetic member are provided in one magnetic member. Also, the magnetic member is held so as to be able to move forward and backward toward the other magnetic member. As a result, since the coefficient of magnetic coupling between a transmitting unit and a receiving unit during charging is enhanced, a charging efficiency can be enhanced.