Since the president Obama took Office，the top priorities of his political Agenda were to rescue the US economy from the global financial crisis and withdraw US troupes from Iraq and Afghanistan. The new Quadrennial defense Review Report，National Security Strategy Report，and National Military Strategy reflected the major adjustment of the US security and military strategy. U.S. national security strategic objective is to renew U.S. global leadership by building at home and shaping abroad. The reform and reorganization of defense institutions demanded to effectively manage risk as a means to rebalance and reform the military in favor of prevailing in today’s wars and dealing with all round of security threats and challenges in the years to come. The new strategy of U.S. requires a portfolio of military capabilities with maximum versatility across the broadest possible range of conflict. The adjustment of US military strategy has very strong implications to the U.S.-China relations. In order to prevent two countries from falling into the security dilemma，the active strategic communication is necessary，and broadening the common and shared interest through cooperation is the right way to keep the bilateral relationship stable and healthy.