A rapid damage mapping with remote sensing and geoinformatics is essential for effective disaster response and recovery efforts. Among the remote sensorsSynthetic Aperture Radar (SAR) is remarkable for its capability to observe the Earth's surface regardless of wheather conditioins. In this paperin order to acquire the mea- sure of building damage level in the tsunami-affected areasthe authors analyzed a set of pre- and post-event TerraSAR-X intensity images. Focusing on the difference (d) and correlation coefficient (r) between backscat- tering coefficients of pre- and post-event images yields good estimation of structural damage with a form of discriminant regression function of d and r, with the accuracy of more than 70 %.