Abstract: Stabilization accuracy of the line-of-sight is one of the key specifications of the remote infrared detection system, which is mainly determined by the servo loop bandwidth and isolation. In this paper the composition of the remote infrared detection system was described, the principle of two-level stabilization techniques based on FSM was analyzed, coarse stable platform electromechanical model, fine stable platform electromechanical model, the optical transfer function model and the control system transfer function were established, through the analysis of bandwidth and isolation transfer function, the boundary conditions of the disturbance compensation were explained in detail, stabilized ability of the two-level stabilization and common stabilization were contrastly analyzed. Simulation results show that the bandwidth of stabilization loop reaches about 200 Hz, isolation is superior to -66 dB at 1 Hz, Stabilization accuracy reached 12 rad by actual test, meet the requirements of remote infrared detection system for stabilization accuracy.