On-ground experiment for space robotic system is essential to validate constructed robotic system prior to launch. This paper presents an integrated on-ground experimental environment for orbital robotic system. The experimental environment utilizes an air-floating testbed to realize two-dimensional micro-gravity environment on ground. As manipulation system, the constructed environment adopts a ground-based manipulator and a free-floating robot. In order to verify the emulated micro-gravity environment, two cases are tested: the impulse-momentum relationship between a ground-based manipulator and a free-floating target, and the conservation of momentum in a free-floating robot. Both results conclude the validity of the constructed experimental environment for on-ground micro-gravity emulation.