Abstract: In this paper the extreme threshold of temperature is defined by the percentile value of time series of daily maximum or minimum temperature,and the annual frequency of sustained extreme high(FSEHT) and low temperature(FSELT) events at least 3 days(1 day interval after 4 days) during 19812010 in Guizhou are analyzed with the ensemble Empirical Mode Decomposition(EMD) method presented by Wu.The results show that during the 30 years,the FSEHT and FSELT series both exhibit a linear ascending and decreasing trend in Guizhou;the prominent positive linear correlation between the FSEHT series and the annual mean temperature series is statistically at the 0.05 confidence level,while changes in FSELT are hardly affected by the annual mean temperature.Besides there are also oscillations of different periods in the two frequency series;and in view of principle periods,the oscillations of the two series are high frequency oscillation.