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By means of the daily observations data of 16 meteorological stations over Hulun Buir from 1973 to 2012, the day to day meteorological drought Composite Index (CI) in the growth season (from April to October) is calculated, and the characteristics of drought strength in Hulun Buir are analyzed. Using the methods of linear regression, signal to noise ratio test, M K mutation testing, and wavelet analysis, the spatial distribution, variation with time, mutation, and periodicity of drought intensity are studied. Analysis shows that meteorological droughts occur most frequently in the pastoral areas, with the strength decreasing from the southwest pastoral area to the northeast forest area; spring droughts have a decreasing trend, while summer, autumn droughts aggravating trends, particularly in the pastoral area in autumn; the variation periods in the agricultural areas are longer, 19 to 24 years, and those in the forest and pastoral areas are shorter, 5 to 12 years and 7 to 12 years.