This paper investigates the underlying China factor that played out when nine countries ended diplomatic relations with the Republic of China (hereafter called 'Taiwan'). Research shows acquiring economic benefits from China, in terms of trade, investment and foreign aid, securing China's support for enhancing international status and consolidating domestic political power are important factors when an ally of Taiwan considers breaking ties. Most allies receive immediate and significant political and economic benefits from China, even those who have been allies of Taiwan for many years, as soon as they severe ties. They can greatly improve their national interests by capitalizing on the Taiwan-China diplomatic battle. Thus, Taiwan cannot win this fight by appealing to morals and ideals. Diplomatic allies are not for sale; Taiwan is only able to rent them for a while. If maintaining the number of diplomatic allies remains a priority for Taiwan, the government needs to come up with more comprehensive, flexible and customized economic incentives in order to(re-)establish diplomatic relationships with target countries.