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In order to study the wind shear characteristics over a plateau airport, this paper uses the data from the Lijiang Airport Automated Weather Observing System (AWOS) and NCEP reanalysis data, as well as 3D data obtained from a wind lidar, to analyze the lowlevel wind shear characteristics of Lijiang Airport on 29 March 2020. The results show that the lowlevel wind shear was mainly formed by the effects of the convergence of the surface isallobaric wind and the enhancement of the turbulence caused by surface warming, as well as the downward momentum transfer. During the occurrence of the wind shear, the lowlevel wind field obtained from the wind lidar was agreed with the surface wind very well. Among the five lowlevel wind shear events, two of them occurred during the orographic wind direction change period from 11:00 to 12:20, and these two are classified as the direction shear of crosswind; the other three occurred from 12:20 to 14:20, which matched with the gradually increasing period of wind speed, and these three are classified as wind speed shear. The wind shear indexes of these five wind shear processes were all greater than 0.1 (1/s), and the shear strengths were moderate or severe, which seriously affected flight safety. The research results provide a reference basis for the laser wind measurement radar monitoring and early warning of airport wind shear.