In order to evaluate guidance radar's anti-jamming performance effectively, a guidance radar RF signal injection system was proposed.The system uses simulator to structure complex electronic jamming environment including clutter, jamming and target echo.Then the system injects the signal into the radar in the form of RF.The test results shows that this guidance radar RF signal injection system can simulate target echo, deception jamming, clutter and barrage jamming, and it can produce signal flexibly.It has great value which matches design requirement well, and satisfies assessment.