In order to reduce the influence of disturbance torque variation on Seeker Servo Control System (SSCS), an adaptive Internal Model Control (IMC) scheme based on disturbance torque estimation is proposed.Firstly, the mathematic model of the SSCS is established, and an internal model controller is designed.The change of the rotating inertia of the SSCS is identified by using the method of disturbance torque estimation.According to the change of the rotating inertia, the parameters of the internal model controller are adjusted automatically by the linear adaptive rate to ensure the control performance of the controller.The simulation and experimental results show that the control scheme has strong adaptability to the change of system working conditions, which improves the anti-interference performance and robustness of the SSCS, and achieves good control effects.