Even though seismic risk assessment is done with a large unit,the actual disaster mtigation countermeasure in residential areas is always done in very small scale.This study established a simulator,with microscopic view,that can show damage of each building,street,and person,and that can explain the effect of small anti-disaster facilities. The authors applied this simulator to an old and densely built and inhabited residential area and analyzed the risk. The simulation showed us that there happen many brocaded street links and many missing people after a large earthquake,and that a small evacuation area doesn't play a role due to collapsed buildings and street blockades.