Abstract: During a long time of a spacecraft staying in its orbit, the accumulation of the interaction between the space magnetic field and the remnant magnetic moment has a great impact on the attitude of the spacecraft. For a 3-axis stabilised spacecraft, there will be an interference torque, which will shift the stable axis of a spacecraft. The attitude control system will have to do extra work, and the reliability of the spacecraft will be affected. The satellite orbit calculation and the geomagnetic field model are used in the numerical simulation of the geomagnetic disturbance torque on the spacecraft. The method for simulating the geomagnetic disturbance torque is finally established for the operation of the spacecraft on orbit.