Based on the 155 years global monthly mean sea surface pressure data(Jan.1850-Dec.2004)from Hadley Centre,the time spatial change and sudden characteristics of the Winter Mongolia High are studied.First,the winter SLP distribution in Asia and the North Pacific are analyzed by the EOF method.Second,main cycle sequences of the Winter Mongolia High are reconstructed by the Singular Spectrum Analysis method,with special emphasis on the interdecadal periodic changes.Finally,the abrupt climate change is examined by the Mann-Kendall method.Results show that the Winter Mongolia High has quasi-biennial oscillation and a 3-4-year cycle of interannual change,also has a decadal variation for the 13-14-year cycle and interdecadal cycles for 20-21years and 35-36 years.The 20-21-year cycle of WMHI is of the opposite phase to Aleutian Low,while the 35-36-year cycle is of the same phase.Otherwise,a significant abrupt climate change point in 1927 has been detected.