Dried simulated radioactive wastes were solidified with thermosetting resin and their properties were investigated with laboratory scale and real scale products through extensive testings, such as mechanical resistance, resistance to leaching and swelling in water, radiation resistance, fire resistance and resistance to temperature cycling. The typical results were as follows: over 600 kg/cm2 of compressive strength, diffusion constant of ֮10−5 cm2/day for 137Cs leaching from solidified waste products, no significant change was found for up to 5 × 108 RAD irradiation, and damages were limited to the surface of the products after the thermal test and dropping impact test.