Abstract: A liquid applicator for the skin comprises a hydrophilic pad for applying liquid on a zone to be treated. It further comprises elements for connecting the pad to a cartridge storing the liquid. The connecting elements are adapted for mounting the pad opposite the liquid flow outlet from the cartridge. The invention is applicable to applicators of liquid disinfectant or of any other fluid active principle. The invention also concerns a first aid kit comprising an applicator and a cartridge initially separate, and a treatment device consisting of the applicator mounted on an initially sealed cartridge.