In this paper, some factors affecting free space optical communication, which is from atmosphere attenuation 、 atmosphere scintillation and light beam deflection because of sway 、 rock and float, and solutions are introduced. 介绍了大气衰减、大气闪烁以及因摇摆、晃动造成的光束偏离等诸因素对自由空间光通信(FSO)的影响以及相应的解决方法。