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Based on the observation data of 88 meteorological stations in Guangxi from 1961 to 2020, the temporal and spatial variation characteristics of the first day of cold dew wind, the first day of 50% and 80% guarantee rates, and the safe heading period of double cropping late rice in Guangxi are analyzed in combination with the data of rice development period. The results show that: (1) In terms of time, the first day of the cold dew wind in Guangxi shows a slight advance trend at a rate of 0.23 days per 10 years (P<0.05), showing an asymmetric W-shaped feature; in space, the first day of cold dew wind in Guangxi is characterized by a “ladder” distribution: early at high latitudes, late at low latitudes, early in mountainous areas and late on flat lands. (2) The first day of cold dew wind in Guangxi has four cycles of 22 years, 12 years, 8 years and 3 years, of which 22 years is the main cycle of the first day of cold dew wind in Guangxi, without obvious mutation. (3) The average full heading stage of double cropping late rice in Guangxi is delayed at a rate of 0.22 days per 10 years (P<0.05), and the frequency of encountering cold dew wind during heading and flowering is 21.9%. It is suggested that the sowing date of late rice should be adjusted appropriately to make its full heading date 3 to 7 days earlier. In order to avoid being affected by the sudden cold dew wind disaster, the middle late maturing varieties of late rice should be popularized carefully in the central and northern regions of Guangxi.