This paper analyzes U.S's relations with East Asian integration(EAI),argues that:U.S can't be excluded outside of EAI, and East Asia is also very important for U.S.;the attitude of U.S. government experienced a shift from opposition to support, and from support to limited support. U.S. concerns closely the development of "De-Americanization",and has taken some diplomatic action to prevent the "Asia Bloc". The author also tries to put forward policy options for China and other East Asian Countries in response to the attitude and policies of the U.S.