In the near future, it is estimated that the TouNankai and Nankai huge earthquake will occurs along the Nankai Trough. The earthquake generates tsunami attack over a wide range such as Seto Inland Sea where is dotted with islets and so many ships are navigating. In addition that many ships evacuate from port areas to safe area when the tsunami attacks. Sea traffic congestion is concerned about in such the evacuation.In this study, first, we analyzed the traffic density in Bisan Seto on the basis of AIS received data. Then we carried out several kinds of preliminary simulation of ship evacuation from tsunami attack in Bisan Seto for the purpose of consideration of evacuation scenarios. An algorithm of collision avoidance by reducing propeller rotation was introduced to the ships evacuation simulation.Finally, it is found that many ships can evacuate to safer place on time when the tsunami attack in Seto inland sea in safe.
