Graft cellulose samples were prepared by three different initiation methods, and the widths of the NMR absorption spectra of samples were measured at various water contents. Samples prepared by both hydrogen peroxide and adsorbed ceric ion methods exhibited maximum widths of NMR absorption spectra at about 10% grafting, whereas the corresponding values for the sample prepared by the conventional ceric ion method were about 30%. Even a minimum value was found on the sample prepared by the latter method. The reason for such different water-binding behaviors of samples is discussed from the viewpoint of difference in the composition of graft celluloses.