This paper investigates the design aspects of a six-degree-of-freedom (6-DOF) full-physics simulation system for spacecraft Guidance, Navigation, and Control (GNC). As space missions continue to grow in complexity, there arises a need for a precise simulation platform to assess performance or validate the efficacy of GNC algorithms. The primary objective of this study is to present a comprehensive physical simulation platform capable of accurately emulating the full-dimensional motion of spacecraft in six degrees of freedom. The proposed simulation system encompasses both translational and rotational motion in three dimensions, facilitating free motion in all six degrees of freedom. Notably, the freedom of rotation about the three axes is achieved through an aerostatic bearing suspension system. The horizontal two degrees of freedom are achieved using heavy-load air bearings operating on a marble surface, while vertical microgravity simulation is achieved through a gravity unloading mechanism. The entire system incorporates real-time computer software for online adjustment of control system parameters. The initial segment of this paper outlines the composition of the system and expounds upon the operational principles underlying the simulation of micro-disturbance forces and micro-disturbance torque in a 6-DOF dynamic environment. A focus is placed on the utilization of vector allocation algorithms to achieve full-spectrum pose control in all six degrees of freedom. Moreover, a detailed analysis of the gravity unloading mechanism composition and the methodology employed for vertical microgravity simulation is provided. Through simulation validation, the proposed design demonstrates its effectiveness in replicating a ground-based environment for the dynamic simulation of micro-disturbance forces and torque across all six degrees of freedom. This development offers a viable avenue for testing, analysis, and crucial technology validation for spacecraft GNC systems.