Abstract: By modeling the signal processing or data steam processing of the key functional modules of radar and radar countermeasures equipment, the radar countermeasures simulation system based on the mechanism of data stream processing can be built as a dynamic closed loop simulation environment of information processing between radar and radar countermeasures equipment to provide a flexible test-bed for researching the anti-jamming performance of radar and jamming performance of radar countermeasures equipment. In this paper, First of all the basic technical ideas of radar countermeasures simulation system based on the mechanism of data stream processing are introduced in this paper. Then the realizing methods of the models combined with some representative examples are also introduced.