Device for treating human keratinous material, in particular with the aid of an electric current. The device includes a reservoir containing a composition, in particular cosmetic or dermatological, to be applied to the keratinous material, a member for dispensing the composition contained in the reservoir, in particular a pump, an end fitting for the application of the composition contained in the reservoir, comprising at least one application member, in particular a plurality of application members, the application member being received in a housing supplied with composition from the reservoir by the dispensing member, the application member being movable in its housing under the pressure of the composition between a first position and a second position, at least one intermediate storage chamber for the composition being delimited by the bottom of the housing and the application member, the volume of the intermediate chamber varying when the application member passes from its first position to its second position.