This paper presents an indirect estimation based active disturbance rejection control (ADRC) for solar sail station-keeping. In contrast to previous applications of ADRC to spacecraft station-keeping the proposed approach estimates the deviation of the orbit state from the reference orbit, instead of estimating the orbit state directly. Since the deviation of the orbit state varies more slowly than the state itself, the indirect estimation significantly improves the estimation accuracy and hence the station-keeping performance. Moreover, this approach enables a large control time step which is two orders of magnitude larger than those in previous applications. This is beneficial to the implementation of attitude control and power consumption in practice. In addition, errors in the optical properties of the solar sail are taken into account which is a major challenge for solar sail station-keeping that has not been considered in previous station-keeping control design. The simulation results show that the presented ADRC station-keeping is robust to errors in these optical properties.