Abstract: The application of quantitative feedback theory (QFT) to design the flight control system combined with active disturbance rejection control (ADRC) algorithm for some missile is studied in this paper. From the results of simulation, the robustness analysis and the comparison of the ADRC and the PID algorithm, it could be concluded that the designed control system has good responses and robustness with satisfactory control performance. The output response overshoot of ADRC is less than PID control, but the rapidity is slightly worse than PID control. The ADRC algorithm to design the height keep loop of the missile longitudinal control system can get good tracking performance. The vertical speed tracking has hardly any overshoot, which shows good dynamic performance and steady state performance.