Gelatin films were prepared from granular gelatin by casting. Gelatin films were modified by photocuring with a trifunftional monomer Trimethylolpropane trimethacrylate (TMPTMA). Optimum condition for photocuring were established. Water aging of untreated and modified gelatin films was studied. Thermal aging of untreated and TMPTMA treated films were determined at different temperatures (50°C, 70°C and 100°C) for 60 min. pH aging of gelatin films were investigated in different pH solutions (3.2, 4.1, 4.8, 6.9, 9.2, 12.2) for 1min. Water aging, thermal aging and pH aging showed that the TMPTMA grafted gelatin films experienced less deterioration of mechanical properties than pure gelatin films.