Abstract: In this paper, the finite difference method for solving NS equations and the Direct Simulation Monte Carlo (DSMC) method are used jointly to calculate the plume impingement on the solar arrays of spacecraft and the thermal effects, on the condition of a single engine working continuously. First, the inner-flow field of the nozzle is simulated by solving NS equations. Then, with the obtained results as the entrance boundary condition, the thruster plume field is calculated on a parallel computer platform and its impingement on solar arrays and the thermal effects are simulated in three-dimensional space. The case of solar arrays with 45 degrees of incline is analyzed in the end.