wThe interaction of thruster plumes with satellite components is investigated, with emphasis on undesirable effects, such as disturbance force/torque, thermal loading, and species deposition in the Korea Multipurpose Satellite-II (KOMPSAT-II) base region. The actual configuration of the satellite is simplified by the consideration of four major components of hydrazine thrusters, the S-band antenna, and the surrounding ring. For the numerical simulation, a fully unstructured three-dimensional discrete simulation Monte Carlo (DSMC) code is developed and validated. The DSMC computation allows for examination of the detailed flowfield dynamics, as well as the wall conditions, which, otherwise, would not be possible from a simplified engineering analysis. The computations show that the present thruster arrangement used in KOMPSAT-II incurs a negligible disturbance force/torque and thermal loading compared with its nominal thrust/torque and solar heating. The simulations also indicate that the species deposition is insignificant due to the high surface temperature of the satellite body. Of the chemical species considered (H-2, N-2, and NH3), more H-2 molecules collide with the S-band antenna cone. This study clearly shows the usefulness of DSMC calculations for analysis of plume effects in the development phase of a satellite.