A undersea earthquake with a magnitude of 9.0 "The 2011 off the Pacific Coast of Tohoku earthquake" took place off the Pacific coast of Japan at 14:46 JST (5:46 UTC) on March 11, 2011. A massive tsunami caused by the earthquake struck the Pacific side of Japan, especially the coasts of Aomori, Iwate and Miyagi prefectures, resulting in a cataclysmic disaster "East Japan Great Earthquake Disaster (Higashi Nihon Daishinsai in Japanese)". This paper describes the fundamental characteristics of Tsunami and the brief overview of the past huge tsunami disasters in Sanriku area. The tsunami damages of the East Japan Great Earthquake Disaster are, furthermore, reported on the base of the field survey, which was conducted from April 4 to 9, 2011 as a group of the 2011 Tohoku Earthquake Tsunami Joint Survey Group of Japan.