The invention relates to a treatment device for dielectric harrier discharge plasma treatment of a wound surface or skin surface, having: a flexible, planar electrode assembly with at least one planar electrode (6, 6′) and a dielectric layer (5) which at least partially embeds the at least one electrode (6, 6′), has a contact side (7) facing the wound surface or skin surface and electrically shields the planar electrode (6, 6′) from the wound surface or skin surface such that only a dielectric barrier current can flow from the electrode (6, 6′) to the wound surface or skin surface; and a control device (2) which has a separate housing (25) and via which the electrode (6, 6′) can be connected to an operating voltage. The treatment device allows simpler wound treatment in that the assembly of electrode (6, 6′) and dielectric layer (5) is designed for uninterrupted contact with the wound surface or skin surface and that the housing (25) of the control device (2) can be fastened with a fastening device (3, 3′) to the body having the wound surface or skin surface.