Abrrroer-ITS data are used mainly in real-time information service at present. The internal relations among them are ignored. In order to use ITS data fully. major characteristics of ITS information are analyzed. A structure oflTS information is brought forward in this paper. which applies data warehouse for decision-making of traKic and transportation management. Main aspects of the model are analyzed such PI subject organization, attribute design, data refinement and online analytical processing. Examples are also presented in this paper.Inder Termx-Data Warehouse, Inlormation Processing, Information Architecture. ITS IhTRODUCTIONnformation is one of the key components in intelligent I transportation systems (ITS). In the existing ITS projects and facilities, data are generated daily and need to be effectively archived. In addition. more ITS projects will be implemented over the next few years. Based on collecting, processing and sharing of information, ITS realizes the shift from the simple and static management into the intelligent and dynamic manazement. It also meets the people's need for real-time and historical traffic information. Vast amounts of traffic data are currently being collected in many urban areas by components of the deployed ITS. At present, the traffic data collected by these systems are primarily used for real-time informalion and operations. Some transportation management centers (TMCs) save or archive the ITS traffic data, but few has a mechanism for exploiting or sharing the data resources among other transportation groups or agencies within the same jurisdiction. Even when TMCs do save data, they face issues related to transforming the significant amounts of data into useful information for adjusting operating strategies, evaluating system performance, or making decisions about future transportation investments. There is an increasing need for managing, archiving and Manuscript received March 24,2003. Qin Xiao-hu is with the Automation