Abstract: With a series of special characteristics, the advanced composite now is not only the paragon of new material development, but also the important research direction of advanced weapon system. In this paper the history of high performance resin matrix advanced composite is first introduced. Then the characteristics of the primary materials used in composites are discussed briefly such as high performance glass fiber, carbon fiber, kevlar, cyanate resin, BMI resin, nomex honeycomb, polyurethane foam and so on. And the actual applications of advanced composite to the radar system are listed as an emphasis, including the radar radome, antenna reflector, feeder, framework, PCB material, stealth material, smart material, etc. Finally it is pointed out that the advanced composite has an extensive application prospect in the radar.