In order to enhance the tracking capability of radar servo system, a radar servo controller was designed based on target information filtering. The stabilization loop was designed with correcting frequency of classical control theory, and by introducing "current" statistical model, with information collected from angle Kalman filter and Doppler tracking loop, the control command of rotational radar was estimated and feedforward control was achieved for angler control. Under 6DOF simulation, it's proved that not only target acceleration's steady-state error was eliminated, but also the angle tracking accuracy of radar seeker was improved.