This paper concerns the control algorithm oriented to nonparallel-ground-track-imaging for agile optical satellite. Firstly, for obtaining the desired trajectory, the mapping relationship between the satellite attitude and the ground stripe is established by using space vector method. According to the mapping function, an attitude adjustment strategy via constant scanning velocity is proposed. Then, considering the exact information of the external disturbance cannot be obtained and the input saturation problem, a robust anti-saturation tracking controller is designed via fixed-time disturbance observer and integral sliding mode. Finally, the effectiveness of the proposed control algorithm is illustrated by numerical simulation. INDEX TERMS Agile optical satellite, nonparallel-ground-track-imaging, integral sliding mode, disturbance observer, input saturation.