The power distribution and comparative strength between countries，especially between big powers，are decisive factors affecting the evolution of international and regional patterns. In East Asia，the changes in the strengths of China and the United States are particularly evident in the “postcrisis” era. While reshaping the regional power structure，these changes have also promoted the emergence of a dualistic regional pattern in East Asia which is featured by the separation of the security center from the economic center. The development trend of this pattern is inseparable from the big powers’East Asian strategies，regional hot issues，and cooperation in security and economy. Although the pattern is playing a role in regional development and overall peace and stability，there is no denying that it also has negative impacts on East Asia regional cooperation. Presently，China and the United States are actively committed to the construction of a new model of China-US relationship，which will release a series of positive effects on the development of the regional pattern，and better promote the pattern to evolve in a direction that is more conducive to peace，development，cooperation，and a win-win situation，a common responsibility of all countries in the region and the relevant international forces.