In a wiper motor including a motor body and a reduction gear apparatus, an accommodating case is integrally provided on a brush holder provided to the motor body, and this accommodating case is disposed on an outer face of a gear case so as to project from a motor yoke. A noise-preventing element including a pair of choke coils and a bidirectional varistor is accommodated in the accommodating case, and the noise-preventing element is connected between a power-feeding terminal of a connector provided on the gear case and brushes. Noises acting on a power-feeding circuit are absorbed by the noise-preventing element and noises which have leaked to the outside via an opening portion of the motor yoke are absorbed by the noise-preventing element.