Abstract: Due to companies’ practical demands for information collection and monitoring around the Internet,this paper firstly proposes the architecture for a distributed environment scanning system,which is based upon multi-agent.Meanwhile,in order to fulfill the special demand of repeatedly gathering updated information,the classical min-min heuristic scheduling algorithm is assimilated to design the recycling task earliest-finished scheduling algorithm.According to the theory of hierarchical timed colored Petri nets(HTCP-net),a system scheduling model is built with modeling and simulation tools CPN tools.Finally,the model executes for simulation and demonstrates the average waiting time of tasks and the average length of each agent waiting queue.Compared with the results from simulations of cyclic scheduling algorithms and shortest waiting queue scheduling algorithms,it is indicated that the scheduling model enhances the degree of organizational users’ satisfaction and also meets the system demands of periodically repeated Web page visit.