Dynamic characteristics and tracking precision are studied in the photoelectric tracking system and a linear active disturbance rejection control( LADRC) scheme is proposed for position loop. A current and speed controller is designed by a transfer function model,which is obtained by adaptive differential evolution. Model error,friction and nonlinear factor existing in position loop are treated as ‘disturbance’,which is estimated and compensated by generalized proportional integral( GPI)observer. Comparative results are provided to demonstrate the remarkable performance of the proposed method. It turns out that the proposed scheme is successful and has superior features,such as quick dynamic response,low overshoot and high tracking precision. Furthermore,with the proposed method,friction is suppressed effectively. Dynamic characteristics and tracking precision are studied in the photoelectric conversion system and a linear active disturbance rejection control (LADRC) scheme is proposed for position loop. A current and speed controller is designed by a transfer function model, which is obtained by adaptive differential evolution. Model error, friction and nonlinear factor existing in position loop are treated as ’disturbance’, which is estimated and compensated by generalized proportional integral (GPI) observer. It turns out that the proposed scheme is successful and has superior features, such as quick dynamic response, low overshoot and high tracking precision.