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The intensity indexes of winter atmospheric circulation teleconnection patterns in the Northern Hemisphere from 1951/1952 to 2002/2003 were calculated and the secular variation and recent characteristics were analyzed. It is shown that the significant negative trend of WA (Western Atlantic) intensity index and the positive trend of PNA (Pacific/North American) intensity index become stronger in the recent ten years. The abrupt changes of their intensities occurred in the early 1980's when WA pattern weakening and in the middle 1970's when PNA pattern strengthening, respectively. The continued strengthening of the winter zonal circulation intensity and the continued weakening of the winter meridional circulation intensity were observed in the area of Asia and Eurasia in the recent ten years. This interdecadal changes of atmospheric circulation and teleconnection pattern intensity are one of important causes of climate changes over China in winter.