Over the past year，China faced four challenges in terms of maintaining its border security. First，the United States strengthened its rebalancing strategy，which led to problems in Sino-U.S. relations. Second，the Abe government in Japan pursued a policy to contain and isolate China，which led to a serious deterioration in Sino-Japanese relations. Third，because of intervention by extraterritorial powers，marine territorial issues became increasingly complex and intractable. In addition，some serious frequently occurring issues weakened stability in China’s surrounding situation. Overall，although China’s periphery environment remained relatively stable and the maintenance of normal relations and cooperation were still a mainstream trend between China and its neighbors，the difficulties faced by China to maintain its border security and stability increased.