Abstract
Liquefaction occurred on 11th March 2011 caused a lot of damage in the Chiba bayside region. In the Urayasu City locates on the bayside, the 51% of the population and 86% of the gross area suffered damage from the liquefaction. The value of a real estate in possible liquefaction area is affected by the efficiency of the property against the liquefaction and the possibility of the earthquake. The reduction rate of the property which has no special efficiency against the liquefaction is less than 9% of the value if the earthquake would happen after thirty years. The pre-precaution against the liquefaction is more effective than restoration work which will be required after the disaster.