Abstract: Aiming at improving the dynamic performance and robustness of two-axis seeker servo system, this paper proposed a method without relying on initial errors. By designing a new performance function, the limit of initial errors has to be known was canceled, so the controller design was simplified. Aiming at the problem of composite disturbance and parameters perturbation as well as the requirement of high tracking precision, the prescribed performance control applied in this paper limits the angle and angular velocity tracking error within the predefined function bound, thus, the steady and dynamic performance of the system were guaranteed. Stabilized analysis based on Lyapunov theorem was carried out, the stability was guaranteed. Simulation shows that the method in this paper possesses strong robustness and high precision, the tracking ability of the system is promoted. Furthermore, the structure of the algorithm is simple, the application potential is broadness.