Abstract: During the service process of spacecraft such as satellite, conductive slip ring-electric brush system is affected by the multi-physical field, and the serious problems such as arc erosion, abrupt change of electrical signal, friction and wear will occur. Focusing on the special working conditions in space, this paper conducted the research on the multi-physical field coupled modeling and service performance analysis of the conductive slip ring-electric brush system. To obtain the input parameters for the simulations of the electrical contact, the friction and wear test device developed with rotational motion was adopted to measure the contact resistance and friction coefficient under different installed loads. On this basis, the finite element model of the conductive slip ring-electric brush system was developed and solved to reveal the multi-physical field mechanism of the components and the influencing characteristics of several factors considering rotational motion, electrical contact, large deformation and heat transfer. The simulation results indicated that, the maximum Mises stress of the conductive slip ring-electric brush system occurred in the reed of the electric brush near the mounting surface, which increased with the increasing installed load. By comparing the transient characteristics of the components, it was found that the heat generation from electric current dominated in the thermal performance of the system, while the effect of friction heat was relatively small. However, the friction force between the interacting surfaces could dramatically change the stress distribution of the electric brush. In addition, owing to the combined influence of the friction and the electric current, the maximum temperatures of the slip ring and the electric brush decreased at first and then increased with the increasing installed load. With the demand of the conductive slip ring-electric brush system developing for long life and high reliability, the research of this paper could provide theoretical support for its further optimization. To reduce the risk of fatigue failure of the system, the reed of the electric brush near the mounting surface needed to be strengthen. Excessive temperature rise in the structures might greatly affect the service performance of the system, and a middle installed load was suggested based on this consideration. To improve the thermal performance of the system during operation, it was better to take measures to reduce the contact resistance between the conductive slip ring and the electric brush.