Recently, the amount of the data measured by the satellites becomes increase because the recent satellites have been higher performances. Therefore, the faster communication method is demanded. One of the solutions is to use optical communication systems. When widely available fiber optical devices are used in free-space laser communication systems, it is required to couple the laser beam into a single mode fiber. Free-space laser communications systems require the precise tracking control because of very narrow laser beams. It is rather difficult to couple the laser beam into the optical fiber owing to atmospheric turbulence in ground-to-satellite laser propagation paths. We developed a simulation model of the fiber coupling efficiency for ground-to-satellite laser communication links under atmospheric turbulence. And we developed a prototype of the fast steering mirror (FSM) which can operate at high frequencies under the atmospheric turbulence. We experimentally verify the tracking performance of FSM by using ground-to-satellite laser communication links.