Abstract: Based on daily maximum and minimum temperatures at 149 stations during 1961-2016, Pacific climatic factor and NCEP/NCAR reanalysis data were analyzed based on Transformed-Stationary analysis method, hierarchical clustering with spatial constraints, MM-K (Modified Mann-Kendall) trend analysis and EOF (empirical orthogonal function). In this study the spatial and temporal characteristics of extreme temperature in the Huai river basin were analysed and revealed the impact of extreme temperature. Results indicated that: (1) The annual maximum temperature (AHT) have an increasing trend in 1960s and 2000s, but the AHT was decrease trend from the 1970s to the 1980s. However, the annual minimum temperature (ALT) in 1960s showed a decreasing trend, and The ALT are in increasing trend after 1970 (the increasing trend is significant at >95% confidence level after 2000). (2) AHT of return period in zone 1 and zone 3 show the stationary characteristics, and AHT of return period in other stations increased by 1.5℃. The ALT of return period had an increasing trend from 1978. The closer the AHT is to the ocean, the more significant the increase trend will be. (3) In the northeast and southeast of the Huai river baisn, the increasing trend of AHT are mainly distributed in the central and western. While the spatial distribution of ALT is the opposite of that of the central and western regions. (4) The North Pacific sea level temperature anomaly (STA) changes significantly affect the Huai river basin in Summer. Extreme temperatures of the non-stationary change have positive related to the western Pacific and north Pacific and negative correlated with the eastern Pacific. From Winter, the land temperature anomalies (LTA) synchronized with the STA in the Bohai Sea and with the changes of El Nino or La Nina. The LTA in Summer were contrary to those in Winter. The analysis of circulation characteristics shows that Winter warming in the Basin is affected by the warming in northeast China and change in Summer in the Basin is affected by the depression of Qinghai-Tibet plateau and Mongolia.