AbstractWe constructed an information retrieval system using mobile agent technology and evaluated it for safety inquiry at disasters. The reason we used mobile agents is robustness against disasters and decrease of communication load. Failure, shutdown, and recovery of communication lines may occur in a large scale and high frequency at disasters, but the agent software autonomously detours or waits and brings back retrieval results. Retrieval is done from outside to inside of the stricken area. We conducted experiments using the agent method, Client/Server (C/S) method, and a combination of the two, and evaluated the results based on traffic amount and response time. We verified that information retrieval by mobile agents has robustness against disasters, and becomes more effective in order to decrease traffic on terminal lines compared with C/S method, as the number of retrievals and the number of migrated servers get larger. © 2002 Scripta Technica, Electron Comm Jpn Pt 1, 85(6): 53–63, 2002