Effects of ,60,Co γ-rays irradiation on protein, amylase, total amylum, amylum viscosity chart, gel consistancy of rice (glutinous rice, japonica rice and early indica rice) were studied. The results indicate that after the irradiation treatment by the dosage of 0.5~7 kGy irradition, the contents of amylum, gel consistency obviously decrease with increment of the irradiation dose. And the peak paste, hot paste and cool paste of amylum viscosity chart also decrease with increment of the irradiation dose. The results show that the irradiation dose for eliminating pests of rice should be controlled under 3 kGy.