Vietnam has officially completed the bilateral negotiations with members of WTO on May 31, 2006. One of the commitments was to open the national financial market. In recent years, Vietnam has become the most popular market for Taiwanese banking to internationalize and expand their business due to the following reasons: the unopened financial market in China, the close relations between the financial industries in Taiwan and Vietnam, and the mission of ¡§Passing Experiences¡¨ by the officials of the Financial Supervisory Commission in Taiwan. Many Taiwanese banks have already set up branches or offices in Vietnam. Moreover, Cathay United Bank has cooperated with the national Incom Bank in Vietnam to establish the Indovina Bank. Vietnam has become one of the main profit-making overseas countries beyond Hong Kong, in the banking industry. According to the statistics, from 1988 to 2006, the investment of Taiwanese companies in Vietnam exceeded eight billion USD. Taiwan was the biggest foreign investment country in Vietnam. Vietnam has opened the flotation of foreign investment in recent years, and Taiwanese investment is the major source. Vietnam has become another main market for Taiwanese companies. On the other hand, these companies are the basic clients for Taiwanese banks in Vietnam. The study has taken Taiwanese banking as the main theme to discuss and analyze the entry models into the Vietnamese market to determine the possible problems and difficulties. Chapter II discusses the related theories and models of multinational companies in overseas markets. It also explains the internationalization process of banking, product lifespan and marketing strategies. Chapter III explains the recent economic development and investment environment as well as the present financial situation and banking regulations in Vietnam. Chapter IV discusses the banking business in Taiwan and investment in Vietnam. Chapter V analyzes all of the collected information and summarizes which models should be followed when entering the Vietnamese market, based on different competition advantages and entry timing of banks. Marketing strategies are also discussed. Chapter six is the conclusion and provides suggestions.