Abstract: A virtual space information processor provides data relating to a virtual space to a plurality of client terminals on a real-time basis. All modules for processing all of the data defining the virtual space, and requests from the client terminals are pre-loaded on a memory. The modules include at least a request-storing module which stores more than one request from the client terminals and a space definition data-updating module which updates, according to the requests from the client terminals, the data defining the virtual space. The space definition data-updating module does not start processing of requests from other client terminals until the processing of the request from one of the client terminals is completed. Besides, the virtual space information processor includes a request processing control module which selects an appropriate module for processing a request stored in the request-storing module and instructs the selected module to process the request.