The UAV has large maneuver and angular velocity motions, which puts high requirments on the servo tracking accuracy of the ground search and tracking system. In order to improve the tracking accuracy of the ground search and tracking system, servo feed-forward compensation technology is often added. Accurate target velocity and acceleration estimation becomes the difficulty of feed-forward compensation control. IMM Kalman filtering is used to estimate the velocity and acceleration information of the target, and it is used as the input of servo feed-forward compensation system to eliminate the miss distance error caused by the velocity and acceleration of the target. The actual system test results show that the tracking accuracy of the search and tracking system is more than three times higher than that of the conventional Kalman filter compensation by using the IMM Kalman filter feed-forward compensation technology, and the model verification is effective.