Gelatin-polydimethylsiloxane (PDMS) graft copolymers were prepared through the reaction between gelatin and alpha-[3-(2,3-epoxypropoxy) propyl]-omega-butyl-PDMSs. The copolymers were characterized by FTIR and (1)H-NMR spectra. As proved by wide angle X-ray analysis, a new characteristic crystalline peak appeared after the bonding of PDMS to gelatin chains. The microstructure and the elemental identification of gelatin and copolymers were followed through scanning electron microscope with energy dispersive spectrometer. The glass transition temperature of gelatin and copolymers were obtained by differential scanning calorimetry analysis. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 120: 2130-2137, 2011