美國與中共是目前全球最重要的兩個國家。由於歷史與地理因素,台灣過去與未來的發展都深受美中台三邊關係的影響。本研究的目的在分析與比較陳水扁政府與馬英九政府時期複雜的美中台三角關係。本論文採取戰略三角模型研究後發現,在扁政府時期,美台關係在小布希政府初期處於良好的狀態,並視中國為美國的戰略競爭者。但是在紐約的九一一恐怖攻擊後,小布希政府改變了其國家安全戰略,並改變了其對中國的政策。同時,由於扁政府操弄選舉策略、美台關係及兩岸關係,使得在扁政府第二任末期美台及兩岸關係處於緊張狀態。在馬政府上台後,由於其大陸政策同時受到北京及華府的歡迎,故而美中台三邊關係處於1949年以來的最佳狀態,而馬政府時期的台美與兩岸關係也遠比扁政府時期為緩和。 The United States and the Peoples Republic of China are two of the most important countries in the world. Because of the historical and geographic reasons, the development and future of Taiwan was and will be deeply influenced by the U.S.-China-Taiwan triangle relations. The purpose of this research tries to analyze and compare the complicated relations U.S.-China-Taiwan triangle relations during the Chen Shui-Bian and Ma Ying-Jeou governments. By adopting the strategic triangle model, this study finds that during the Chen’s government, the U.S.-Taiwan relations were very good in the beginning of the Bush administration, and the Bush administration see the PRC as strategic competitor. After the 911 terrorists attack of New York, however, the Bush administration changes its national security strategy, and also changes its China policy accordingly. Meanwhile, because of the irresponsible electoral strategies and manipulations, the US-Taiwan and the cross-strait relations are tension in the end of Chen’s administration. After Ma Ying-Jeou taking over the presidential office, his mainland policy is welcomed by the US and the PRC simultaneously. Therefore, the triangle relations are in the best situation since 1949, and the US-Taiwan and the PRC-Taiwan relation are smoother during Ma’s government than Chen’s government.