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To accurately evaluate wind shear characteristics in the plain and lake areas of Hubei Province, the paper uses hourly wind data from 27 wind towers with the height between 120 m to 150 m and researches mainly on the temporal and spatial variations. The results show that: (1) The wind shear indexes have prominent characteristics in seasonal and diurnal changes. The wind shear indexes are generally minimum in autumn and winter, larger in summer, larger at night and smaller in the day. (2) The annual average wind shear index of 70 to 120 m is 0.27 in plain and lake areas and 0.12 in mountain areas. The wind shear indexes of each tower decrease gradually from 70 m to 150 m. (3) As for the wind shear indexes of 6 typical wind towers, the frequency of the relatively stable condition is the highest, which is 59% to 75%, and the lowest under unstable conditions, which is no more than 5%. (4) As for the wind speed ranges of 0 to 3.0 m/s, 3.0 to 10.0 m/s and above 10.0 m/s, the wind shear indexes gradually increase. The wind shear indexes in the wind speed range from 3.0 to 10.0 m/s are closest to the annual mean wind shear index, and the wind shear indexes above 10.0 m/s have the stronger dispersion. (5) The measured and simulated wind shear indexes are calculated, respectively. The measured values in the central plain are significantly higher than the simulated values, with the overall deviation ranging from -0.06 to 0.14. The conclusions of this paper can be used to calculate or revise the wind speed at different heights in the low wind speed area in the surface layer to improve the accuracy of wind energy resource evaluation, development planning, wind farm site selection and wind power prediction in this area.