In consideration of effect of intensity scintillation, phase distortion and transmission direction changes caused by atmospheric turbulence on communication links, this paper explores the correction technology of the atmospheric turbulence by the adaptive optics (AO). The correction effects of the AO on atmospheric turbulence in the waveband of free-space communication was analyzed quantitatively. A field experiment to observe the star with different altitude angles in the 1 550 nm waveband was performed with a 1.8 m telescope mounted on Yunnan and the 127-actuators AO system developed by the Institute of Optics and Electronics, Chinese Academy of Sciences. The Strehl ratio and the atmospheric coherent length were recorded for the observation of each star. The experiment results show that when the atmospheric turbulence intensity D/r0(1 550 nm) is less than 6.5, the wavefront error will be less than 1 rad after correction by the AO. It concludes that the AO is able to overcome the effect of the atmospheric turbulence on the required quality of free-space coherent laser com-munication under weak and moderate turbulence conditions.