A large tsunami was induced due to an M8.3 earthquake generated in a subduction zone off Samoa Islands in the South Pacific Ocean, at 6:48 on 29 September 2009 (local time). The American Samoa, Samoa and Tonga Islands had suffered serious tsunami damages and more. More than 120 persons were suffered to death.
　Port and Airport Research Institute dispatched a filed survey team as one part of the international survey team to Samoa to investigate characteristics of the tsunami and the induced damage.
　Heavy damages were caused in the southern coast, while the damage level was not so severe in the northern coast. Especially in the south-eastern part of the island, more than 6 m tsunami struck and its coastal villages were completely destroyed.
　The following finding is obtained in the survey;
1) The damage level depends on the inundatation depth; Villages are perfectly washed out in the area with the depth more than 5m. In case of 4 to 5m inundation depth, villages are partially damaged. The area where the inundation depth is smaller than 3m has little damage.
2) Almost residents evacuated after their watching tsunami or their hearing tsunami noise. Installation of evacutation center near to residents is very important. The education and disciplines in erarly evacuation are also necessary to reduce victims.
3) Improvement of warning system and maintainace of seawall are important because tsunami arraival time is very short afeter earthquake shaking.