Abstract: In order to study the Tongliao extreme temperature for the growth of crops, and the influence of the stable grain production for high yield and provide basis for climate, the use of domestic seven station 52 years (1959-2010) daily temperature data of crop growth season (May - September) average highest temperature, average minimum temperature, daily range of temperature the climate characteristics of analysis. The results showed that, the highest temperature and the average Tongliao City average minimum temperatures were rising trend, all at 0.01 significant level above, three elements were in line with Hurst phenomenon, H index which was more than 0.5, were 0.7946, 0.9024 and 0.9751. Future short time average highest temperature and average minimum temperature would keep rising trend, daily range will remain trend of decrease.