Japanese traditional clay wall on bamboo lathing was investigated that damaged by Kamishiro fault earthquake in Nagano prefecture on November 22, 2014. We confirmed damage states and revealed materials, plastering methods and the lath configurations of the clay wall. As a result, the resistance mechanism against the earthquake was confirmed. Causes of the delamination of the front and back sides of the clay wall layers were revealed; without gaps between bamboo lath and timber framework, falling batten or bamboo lath from timber framework, and with weakness of the sticking force of clay wall layers.
