Based on the daily mean temperature data of 19601999 at 175 meteorological stations over China, this paper firstly analyzes the characteristics of the two climate backgrounds( Climate background A contained the years from 1960 to 1989,while the climate background B contained the years from 1970 to 1999) .Monte Carlo significance test method is applied to examine the difference in winter and summer under the two climate backgrounds. Respectively based on the two different climate backgrounds, the study applies climate percentile method to analyze the variation characteristic of the extreme temperature over China from 2000 to 2010.The result showed that the difference of winter average temperature under the two climate backgrounds is more significant than the difference in summer. The extreme low temperature events in winter ( summer) happen less frequently than extreme high temperature events in winter( summer) over China.Because the climate background B contained the years from 1980 to 2000 and the global warming was most serious during this period,when we use climate background B as the background during 2000-2010, the extreme low temperature events in winter( summer) happen more frequently than using climate background A as the background.The situation of extreme high temperature in winter( summer) is contrary to the situation of extreme low temperature events in winter( summer) from 2000 to 2010.These results are consistent with the trends of global warming.