The Center for Conservation Science and Restoration Techniques is also examining the extent of deterioration of wooden buildings in the project “Study on assessment of influence of ambient environment on cultural heritage and countermeasures.” Among the wooden buildings subject to a severe outdoor environment, particularly the Itsukushima Shrine in Miyajima-cho, Hatsukaichi City, Hiroshima faces stern conditions, such as harsh weather and the influence of seawater. It is affected by intense UV rays, wind, rain, seawater and waves, and was also heavily damaged by gribbles and shipworms under the sea. We are now studying how to prevent the wood from deteriorating in this situation, and how to restore the deteriorated wood and what restoration materials to use. Therefore, we are conducting physical tests such as a strength test, curing test and exposure test in various forms at the local site. In this way, we are investigating the optimum techniques to use. We hope that the results obtained by such examinations will be adopted for other wooden buildings.