In view of missile autopilot design, the performance analysis method of actuator was discussed. The demand of actuator angular and angular velocity was deduced. The difference of actuator and actuator model was analyzed in this paper. Actuator performance was gained approximately by collecting information from actuator test data. Whether the actuator system is meet the need of autopilot was estimated. The exact linearization simulate actuator model was tried. By studying actuator nonlinear element, the measures to eliminate and weaken the influence of actuator nonlinear element were estimated. In this way, the work of designing autopilot was supported by the data in this paper. The result of simulation demonstrates the effectiveness of this technique.