West off Fukuoka prefecture earthquake with magnitude of 7.0 occurred at northwest part of Fukuoka city on March 20^th 2005. Many building structures had heavy damages. This paper deals with the damage of building structures in Genkai Island, Shika Island, Itoshima Peninsula near the hypocenter and Daimyo area near Kego fault. Fortunately, A seismically isolated building was Daimyo area. Observed earthquake response of the building is analyzed and discussed in this paper.