Tsunami disasters are not necessarily very few events in the Asian coastal areas and yet they are not well recognized by the people living in the coastal areas. The tsunami disaster in 2004 triggered by Sumatra Earthquake proved that the people in the coastal areas should have reasonable degree of basic knowledge what tsunami is all about. The public education performed in Japanese primary schools during a period of 1937-1947, to introduce the children what the traditional disaster mitigation and rehabilitation measure are, helped the Japanese people have an idea how to save themselves when tsunami could sweep the shores. This paper describes an event related to a tsunami disaster in one of the coastal areas in Japan and how it was introduced to the primary school children in Japan.