An electric power-feeding structure for feeding electric power to a moving body which is driven to be raised or lowered, includes: an arm having a distal end connected to the moving body movably in a direction perpendicular to a raising or lowering direction of the moving body and a proximal end adapted to be rotatably driven so as to swing, to thereby drive the raising or lowering of the moving body. An electrical wire is routed alongside the arm, and one end of the electrical wire extending from the distal end of the arm is connected to the moving body to feed electric power to the moving body. The electrical wire is routed alongside a side surface of the arm.