Optical wireless communication has several advantages.It has become a viable tool to solve "last-mile" and been considered one of development direction of the next generation optical communication.The history of the development of the optical wireless communication is reviewed firstly, and then, the atmospheric effects to the laser wireless communication link near the earth are elaberated and the emphasis is the atmospheric degradations and turbidity effects. Finally, the scintillation is simulated and the future is forecasted.