The inactivation of bacteria and viruses by heating is currently an effective method for the disinfection of bone allografts. The condition as the relation between temperature and processing time, such as 80℃ for 10 minute is recommended for heat treatment in the Japanese Orthopaedics Association. We already investigated to measure bone thermal characteristic and response to microwave heating. Our experimental results suggest that thermal processing for disinfection using microwave irradiation will heat the bone from inside more and with a more homogeneous temperature. The purpose of this study was to investigate on biomechanical properties of microwave-irradiated bovine cortical bone. The bone which irradiated microwave did not accept a statistical significant difference in compressive strength, maximum strain and Yang's modulus as compared with control. The bone fell 4.1% by the Vickers hardness number. The biomechanical properties of the bone are maintained and it is possible to use it as bone allografts.