Hall thrusters, a type of electric propulsion, are increasingly being used as propulsion systems for spacecraft. When evaluating the performance of a Hall thruster through ground tests, it is essential to recognize the influence of the higher background pressure inside the vacuum chamber compared to space conditions and to correct the performance values to reflect those in actual space environments. In this study, the effects of background pressure levels ranging from 3 to 60 μTorr on the exhaust plume of a Hall thruster were analyzed using PIC-DSMC(Particle-in-Cell Direct Simulation Monte Carlo) method. It was observed that as the background pressure increased, collisions and charge exchanges between neutral atoms and ions in the thruster plume increased. With the increase in charge exchange, the scattering of Xe+ ions and the plasma potential also increased, leading to an increase in ion backflow. Therefore, correcting the results considering background pressure is essential for accurate performance prediction of electric thrusters.