<p>The probability of Nankai Trough earthquake occurring within 30 years is estimated to be 70% to 80%. Its damage would be extremely extensive and devastating. It is necessary to quickly transport a large amount of relief supplies after the disaster. Japanese government and minicipality are planning transporting disaster relief supplies. The transportation by ship is supposed to be carried out mainly when the truck transportation does not function sufficiently. On the other hand, there is a high possibility that truck transportation capacity will be insufficient because of road network damage and shortage of available number of trucks and so on. It is meaningful to evaluate the transport potential of a ship as a redundant system. In this study, we evaluate the availability potential of coastal ferry/RORO vessels for transporting relief supplies after the possible largest scale of damage in the Nankai Trough earthquake by using AIS and vessel attribution data. As a result, it was found that the ship has high transportation potential even after the Nankai Trough earthquake.</p>