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The statistical characteristics and variation of climatic elements are analyzed on the basis of the meteorological observation data corresponding to the relevant periods of winter wheat growth from 1954 to 2007 in the southwestern Shandong Province, and the impacts of climate warming on the seeding time and overwintering period of winter wheat are studied with the correlative analysis method. The results show that compared with the period before 1980, the average air temperature at the seeding time of winter wheat increased by about 0.5 ℃, and the prewinter accumulated temperature increased by 17.8 ℃. The average air temperature in the overwintering period of winter wheat increased by 1.0 ℃. Owing to the combined impact of climate warming and variety renovation, the appropriate seeding time for winter wheat advanced 7 days or so compared to that before 1980. The findings provide references for ascertaining the appropriate seeding time, decreasing freezing damage, and growing strong seedlings of winter wheat.