Potential applications of irradiation technology inpostharvest handling of agricultural products have been documented over the past five decades. The biological effects of ionizing radiation on food were demonstrated to have the potential both of reducing the storage losses by controlling spoilage microoraganisms, insects, to have the potential both of reducing the storge losses by controlling spoiliage microorganisms, insects, sprouting and ripening, and of improving the hygienic quality of raw and processed products. Food irradiation is recognized as a physical and cold process using gamma-rays from radioisotope sources and electron-beam from the accelerator. As one of the technologies or techniques for preserving and improving the safety of food, irradiated technology has been approved in some 40 countries for more than 200 individeual items of foods and of these about 30 countries including Korea are commerically utilizing this technology. Although limited quantities of irradiated foods are available in the market now, the proper uses of this renewed technology will offer great possibilities not only for increasing the availability of postharvest agricultural products, thereby contributing to price stabilization in the off-season, but also for reducing reliance on chemicals used for sanitary and quarantine requirements. This paper deals with biological actions of ionizing radiation and its potential applications in the agri-food industry from the international point of view.