Abstract: Aimed at the electromagnetic compatibility(EMC) problems between same working band radars on fleet battle ships, radar detection performance such as maximum radar range is used to describe the EMC degree between the radars in radar system. The EMC degree model of entire radar system can be gotten by establishing EMC model of every two radars. Through the simulation, the relationship is analysed between the degree of EMC and several important parameters in the model such as the distance between the radar and so on which provides a digital basis for analyzing maximum benefit of the radar in coordinating combat.