The treatment of cellulose with cold plasma in the presence of two silanes is found to be efficient in the grafting of cellulose macromolecules. The occurrence of the grafting is proven by contact angle measurement, ESCA, and SEM. Thus, after plasma treatment the polar component of the surface energy of the treated samples decreases from 23 mJ · m−2 to practically zero. The ESCA spectra showed the appearance of two new peaks at 102 and 150 eV, relative to the presence of Si atoms and a substantial increase in Cl signal, attributed to the enrichment of the surface by CH moieties borne by the silanes. SEM confirms the presence of the silane, both in the bulk and at the surface of the treated samples.