Abstract: Cross-linked fibroin gel was prepared with polyethylene glycol diglycidyl ether(PGDE) as crosslinking agent.The thermal stability of fibroin gel as a function of fibroin concentration,PGDE concentration,NaCl concentration,and reaction temperature was measured by differential scanning calorimetry(DSC) analysis.The results indicated that the thermal decomposition temperature keeps rising with the increase of fibroin concentration and reaction temperatures,and as the concentration of PGDE and NaCl increases,it goes up to a certain extent,then drops slowly.