To mitigate severe traffic confusion in the aftermath of an earthquake, the transportation management through the use of computer aided system is needful for government’s measures. Thus, a evaluation system based on the GIS and road network database has been developing in Tokyo Metropolitan Government. The system, which employs the flow dependent traffic assignment, estimates the maximum road network capacity with variable demand (namely, elastic demand) under any damaged network. Several categories of information, which are obtained from the system, can offer the efficient methods for transportation management.