The aim of this research is to assess the possible impact of the WTO on economic institutional changes, FDI inflows, and exports and imports of Vietnam. To achieve reliable and persuasive outcomes and to enhance the significance of the research, the author will employ the gravity model using the Hausman-Taylor (1981) estimator and updated figures from trustworthy sources (e.g., WTO negotiation documents of Vietnam, relevant research papers, state agencies and international organizations such as the Asian Development Bank (ADB), the International Monetary Fund (IMF), the World Bank (WB), etc.) for the empirical analysis in this research. This research should be especially useful to professional in international economics field, or anyone else who may be considering evaluating the impact of the WTO and FTAs on FDI flows and foreign trade of the member countries.