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The 2011 off the Pacific coast of Tohoku Earthquake of Mw=9.0 with a huge source region of about 450km by 200km caused extensive damage of various structures. Damage caused by tsunami was tremendous and a lot of lives were lost. Besides the damage of concrete structures, seawalls were seriously damaged probably due to scouring. On the other hand some reinforced soil walls were found to be damaged little, though they were inundated with tsunami. This paper briefly reviews the reinforced soil walls in Japan first, then reports the summary of seismic performances of about 1600 walls in the 2011 Tohoku earthquake. It also reports some case histories on the reinforced soil walls which were subjected to the direct impact of the earthquake (shaking) and the tsunami. Just less than 1% of the walls were seriously damaged but more than 90% of the walls did not show any damage. However, some damage was found at the backfill and facing panels where the soil was not properly covered and protected against erosion by the tsunami.