The existence of regimes on foreign direct investment (FDI) in the Chinese triangle (China, Hong Kong and Taiwan) is one of the most important elements that promote rapid FDI inter-flows and economic integration within the triangle. The economic policies and FDI inter-flows are leading to their regimes harmonize with international standards. Cultural backgrounds and ideological conflicts have an impact on shaping legalism towards their FDI regimes. Their FDI regimes also reflect the interaction between market and government. As their domestic markets being oriented toward a bigger and more competitive international market, FDI regimes in the triangle need to be, at least, harmonized with each other and with international standards. Learning from East Asian countries' past examples of rapid economic growth and recent lessons of financial crisis, governments within the triangle need to improve their FDI regimes to support the Chinese triangle to be more dynamic and harmony. In this thesis, after exploiting the backgrounds of FDI regimes in the triangle, I first compared the systems and effects of FDI regimes in the Chinese triangle, then analyzed their integration and harmonization trends. In conclusion, both market mechanisms and government strategies can and have played an important and effective role in the triangle in building regimes to attract FDI inflows to support their economic development and integration with each other. Meanwhile, as part of their legal systems that belong to three major different legal systems in the world, the integration and harmonization of FDI regimes in the triangle could be a useful preparation for the harmonization of international investment law.