Hydrogen and oxygen plasma treatment of two cellulose materials, a filter paper of pure cellulose and a greaseproof paper with a fairly high surface content of wood resin, has been studied with ESCA as well as by contact angle or water adsorption. The hydrogen plasma treatment reduces the hydroxyl groups on the cellulose and creates low molecular weight materials. Due to the lower polarity, water adsorption is reduced. The oxygen plasma treatment of the pure cellulose both oxidizes and reduces the surface. The resin-rich paper, which has a hydrophobic nature, shows improved water wettability after both hydrogen and oxygen plasma treatments.