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Daily temperature of 88 national meteorological stations in Guangxi from 1960 to 2019 are utilized in the research. The study period is divided into two stages: the first 30 years (P1: 1960-1989) and the last 30 years (P2: 1990-2019). The annual variation of the safe sowing date and safe transplanting date of early rice, safe full heading date and safe maturity date of late rice is analyzed. Differences in safe production dates under different guarantee rates in P1 and P2 stages are compared. The aim is to analyze the impact of climate warming on the safe production dates of doublecropping rice in Guangxi. The results show that: (1) The safe sowing date and safe transplanting date of early rice showed a trend ahead of time. The safe full heading date and safe maturity date of late rice showed a trend of delay. The safe sowing date and safe transplanting dates of 80% and 90% guarantee rates were advanced by two days on average. The safe full heading dates of 80% and 90% guarantee rates were delayed by two days on average. On average, the safe maturity dates of 80% and 90% guarantee rates were delayed by five days and six days separately. (2) The results show that the spatial differences of variation characteristics of safe production dates were significant. The safe sowing date and safe transplanting date advanced by more days (above six days) in the northeast of Guangxi. The safe full heading date was delayed by more days (above six days) in Napo and Jingxi of Baise. The delay days of the safe maturity date were six to ten days in most areas of Guangxi, and the spatial differences were relatively small.