By employing the CCM3(R15L9) long-rang spectral model developed on the basis of CCM3 climate model,study is undertaken of the effects of the persistent positive sea surface temperature anomaly(SSTA) in the Northern Pacific ocean on East Asian atmospheric circulation in the early summer.The results indicate that the persistent positive SSTA in the North Pacific indues the warming in the middle and upper troposphere in the Asia-Pacific region between 20-40°N,thus favorable to the weakening and north Jump of the East Asian subtropical westerly jet in the early summer,the strongthening and northward advance of the tropical upper-level easterlies and the northwest Pacific subtropical high;and also favorable to the development of the Asian summer monsoon and the surface mean temperature rising overEast Asian land.All those circulation characters are beneficial to accelerating the season transition in East Asia in the early summer.