In the Gobi region of Xinjiang, the system of atmospheric coherent lengh measurement and micro-thermal meter were set up in the surface of lake for measuring atmospheric turbulence. The refractive index structure parameter was used to compute the atmospheric coherence length, the distinctness was analyzed also. The result shows that the time-interval of weak atmospheric turbulence is not obvious at sunset and sunrise in the autumn. At sunset, the time-interval of weak atmospheric turbulence mainly distributes about 9:00; at sunrise, the time-interval of weak atmospheric turbulence mainly distributes about 21:00. In the daytime, The time-interval of strong atmospheric turbulence lasts six to eight hours, and mainly distributes from 12:00 to 20:00. The strength of atmospheric turbulence in the nighttime is obvious stronger in the daytime, it is stabler by in the land.