In order to provide an effective method for traffic operation and evaluating different traffic control strategies for urban freeway network, this paper provides a macroscopic traffic flow simulation system for urban freeway. Whole framework of the system includes input module, simulation module and output module. Then it describes the program process and gives the main technical details via the object-oriented language Microsoft Visual Basic. Finally, taking the example of an urban freeway network with two origins and two destinations, this paper describes the process of generation, spreading and dissipation of the recurrent congestion. Besides, it simulates the effects of the ALINEA ramp metering strategy. Research results show that the system does not only do well in describing the evolution of the network traffic flow, but also testing and evaluating traffic control strategy effectively.