The statistics characteristics of East Asia winter monsoon and atmospheric circulation fields from 1956 to 2005 are analyzed by using the EOF (VEOF) method. Results show that there are two modes in East Asia winter monsoon. The variation of the second mode played a more important role in the interdecadal variations and longterm variations trends of winter monsoon. The interdecadal spatial anomalies of winter monsoon and atmospheric circulation had a sudden change in about 1980. The interdecadal variations of winter monsoon correlate closely to the interdecadal variations of winter temperature and precipitation in China.