The preservation test results of lotus seeds by gamma-ray irradiation technique are introduced. The results showed that the sitophilus, penicillus and aspergillus oryzae caused the great damage of lotus seeds. It was found that the radiation doses of deactivation for the insects and the mould were 0.8 kGy and 5 kGy respectively. The irradiated seeds packaged in the cloth bags and stored in the storehouse were not damaged by the insects and moulds for three years. The measured resutls also showed that the nutrient compositions were not changed and the pathogenic bacteria were not found. The irradiated lotus seeds are healthy and safe to the people.