This research analyzes US interest supporting and protecting Taiwan in conflict between Taiwan and China. In this case, The United States arms sales to Taiwan and helping Taiwan in their military arms, to against and protect threats from China. US providing Taiwan with enough military weapons and communication devices. Gun sales are important components in maintaining peace and stability in cross-sectional relations and across the region. Although conflict of China-Taiwan has abated, US continues the military cooperation with Taiwan. The method used in this research is qualitative research. Some of the data obtained came from books, journals, articles, newspapers, the internet and other media. In this study also uses the concept of Foreign Policy, use of the concept of national interest in looking at the cases studied and use concept Balance of Power. Research shows that the US has an interest in helping Taiwan in the conflict between Taiwan and China. Government of U.S come as international actor who have interest in Taiwan. United states become the state that protecting Taiwan. United State have interest to humanitarian and peacekeeping in Taiwan-China conflict. Behind this humanitarian and peacekeeping interest, US also have a economic and political interests in Taiwan