An electrode for dielectric barrier discharge treatment of a substrate includes a tubular housing that is made of electrically insulating material and has a bottom wall facing the substrate, two side walls extending away from the substrate, and a top wall connecting the distal ends of the side walls. The electrode further includes an electrically conductive electrode member disposed inside the housing and having a plate that engages an internal surface of the bottom wall of the housing. The electrode has two wings formed in one piece with the plate and engaging internal surfaces of the side walls of the housing.