The Northeast Asia geopolitics is changed due to the U.S. Asia-Pacific Rebalancing Strategy and Chinese rapid rise. The paper analyzes the acting of U.S. Asia-Pacific Rebalancing Strategy，on the one hand，the U.S. accepts the result of Chinese rapid rise，respects Chinese core interest. On the other hand，the U.S. tries to maintain its strategic dominant by rebalancing in the area. In the Diaoyu Island Issue，the U.S. tries to balance Japan and China. The paper also analyzes the Six Party Talks，Sino-U.S. Relations in the Northeast Asia，and gives some recommendations on Chinese strategic countermeasures.