Abstract: The magnetorquer is an important component to provide relatively intense magnetic fields in a spacecraft. The produced intense magnetic fields play an important role in the distribution of ambient charged particles. In order to make a quantitative analysis of the interaction between the magnetorquer and the ambient plasma, the finite element method is used to simulate the charged particle traces when they fly towards the magnetorquer based on the coupling model of moving electrons in the magnetic field. From the simulation data, we can see notable deflections in the traces of the incoming charged particles when they pass by the magnetorquer, and this kind of deflection is increased as the incoming particle energy decreases. Because of the deflection, there exists an asymmetric distribution of the charged particles injected to a satellite.