Although 2012 is the 20th anniversary of friendly relations between South Korea and China, it is also the 20th anniversary of diplomatic cessation between South Korea and Taiwan. Looking from the aspect that relations between the two sides continued even after the diplomatic ties of South Korea and China, it is fair to conclude that there is a necessity for research on Taiwan. Then, what significance does Taiwan have to South Korea? In terms of security, Taiwan has four implications. First, Taiwan’s experience in securing stability and peace in Cross-Strait relations through deepening mutual coexistence and economic exchange holds great meaning for South Korea. Second, Taiwan can be the barometer to measure whether or not China will become the hegemony. Taiwan would be a good indicator of whether China will take on the characteristics of hegemony or a righteous leadership at the time they become a G2. Third, Taiwan is a meaningful variable in the security for the Korean peninsula. As a party that is directly influenced by U.S.-China relations, Taiwan is absolutely connected to a part of the peace and security of the Korean peninsula. Fourth, what will Taiwan do in the case that it no longer has a power that will protect its security? Hence, in the case that the U.S. considers Taiwan a strategic burden and does not continue to protect it, what decision will Taiwan make? The U.S.-Taiwan relations is a good comparative case study for South Korea-U.S. relations. These four comparison points are important lessons for the security of Korea. After 1992 and until now, Korea and Taiwan have placed efforts to recover relations. Recently, with the retaking of power by Ma Ying-jeou in Taiwan will be helpful in the progress the relations between both sides. However, as Korea takes the One China Policy and is sensitive on political and security exchanges with Taiwan, exchanges between Korea and Taiwan have been unofficial and limited to non-political exchanges. If these principles are kept there is much to progress in relations for both sides. Through strengthening economic, social, cultural and civilian cooperation between Korea and Taiwan can become more stabilized as well as obtain a more benefits and cooperative area. Through this, Taiwan and Korea will be able to invest a bigger meaning in their existence and as a member of the global community they will be able to take on a more meaningful role.