Taiwanese small and medium enterprises always hold an important role in leading the Taiwanese economic to develop in globalization, creating many job opportunities in the country as the foundation for the social and political stability. But by the trend of worldwide business merging and expanding enterprises scale, small and medium enterprises in Taiwan have to face challenges of upgrading and changing the type of business. To be able to survive and grow, Taiwanese small and medium enterprises must modify their structure, improve technology, conduct automation, even to invest in less developing countries or lower-wage countries such as China and other countries in the region. Since 1988, Vietnam has become a strongly attracting investment destination to Taiwanese small and medium enterprises. Taiwan always leads in the top 3 investors in fields of number of investment projects as well as total investment capital. So the question is why so many Taiwanese enterprises choose Vietnam as an investing destination but not other countries in the Southeast Asian region? Questions such as what advantages and strengths in the Vietnamese investment environment are, what conveniences that they bring to Taiwan businesses, etc ... has become the most attractive themes in Taiwanese corps. This study used case-studied approach, combining direct observation methods to conduct data collection then analyzed to understand the motivation for investment in Vietnamese, investment state and competitive advantages of Taiwanese small and medium enterprises in Vietnam.