Using the Ensemble empirical mode decomposition methods,based on the 50 meteorological stations daily minimum temperature data observed in Xinjiang during the period from 1971 to 2013,which were processed by the National Meteorology Information Center,the spatial distribution characteristics of the first frost dates,last frost dates,frosty and frost - free period in Xinjiang were analyzed,the tendency of them were classified. The results show that nearly 43 years,the trend of last frost date move up was more obvious than first frost date postponed tendency,frost - free period shorter was more obvious than the frosty prolonged in Xinjiang; The trend of first frost day delay,last frost date move up,the extension of frost season and frost - free period shorten are more significant in northern of Xinjiang than in southern of Xinjiang region. The first frost dates advance trend showed in 44% of the area over Xinjiang,the last frost dates delay trend showed in 44% of the area,frost period shorten area accounted for 72% of area,frost - free period extended trend showed in 42% of the area.