The drag-free satellite is a critical platform for space gravitational wave detection missions, and the high control accuracy of the drag-free and attitude control system enables the detection missions. Due to the strong dynamic coupling between test masses and satellite, the ground experiment is a fundamental step for the verification of the applied controller. This study presents a Drag-Free Satellite Hardware-in-the-Loop Simulation (DFS-HILS) system based on the planar air-bearing testbed. Moreover, an extended mechanical structure is designed to achieve actuation of the test masses. Finally, the preliminary experimental results show that designed simulation system and the proposed control strategy can successfully realize the drag-free control and the electrostatic suspension.