In order to solve the problem of tracking fast moving targets, the control technique based on active disturbance-rejection controller (ADRC) of photoelectric tracking was studied. A third-order nonlinear expansion observer was designed based on the speed closed-loop transfer function to achieve a compensation of uncertainties, and the tracking error was improved by transforming the position transfer function. The performance of ADRC was demonstrated by numerical simulation and experiments. Compared with PI controller, the ADRC method shows better performance in the steady-state tracking error, the results indicate that the tracking error is improved by 7 times while the system tracks fast moving targets. Because of friction and noise, the tracking error is only improved by 4 times while the system tracks low moving targets; If phase compensation is introduced in control loops, the overshoot will decline by 40%, which shows higher practical value for the study of high-precision tracking control system.