It is the aim of this study to evaluate the surviving strength of bending or full compression of wood damaged by bio-deterioration. The bending or the full compression performance of the Sugi and Todomatsu specimens damaged by termite attack or brown-rot fungal attack was evaluated, and the threshold value ensuring the standard strength was also investigated. As the results, we suggested that penetration depth of 25mm in the case of Pilodyn®, regardless of the wood species and the type of bio-deterioration, was appropriate as the threshold value in this research. It was also suggested that the enough residual strength was not obtained in the case of the ultrasonic velocity of below 5000m/s for the longitudinal direction in the bending test. But it was difficult to decide the threshold value using the ultrasonic velocity for the tangential direction in the full compression test.
