The interaction between the plume of Hall thruster and the surface of the SMART-1 spacecraft is investigated by developing a three-dimensional IFE-PIC-MCC code, with the emphasis on the effect of the disturbance force and thermal loading caused by charge exchange ions (CEX) impingement on the surface of the spacecraft. The parameters such as heat flux and forces of CEX ions which impinge on SMART-1 and solar arrays are obtained. The disturbance force of CEX ions to the spacecraft is calculated for different divergence angles and different solar array rotation cases. The simulation results show that the disturbance force and heat flux on spacecraft change very little as the divergence angle changes. The effect of maximum disturbance force can be neglected since it is so small comparing with the nominal value of the main thrust. Solar arrays receive the least thermal heating from the CEX ions when the beam ions flow is perpendicular to the solar array plane.