The greatly improved investment environment of China is the main reason for successful investment attraction. Investment environment is the primary condition to motivate investment. The capital of transnational corporations is prone to flow in the countries and regions with huge market potential, low cost, good infrastructure, and a stable society, so that the safety of investment and stability of vigor can be ensured. In the past few years, transnational corporations have increasingly augmented their investment in China. The most important reason lies in the huge market potential brought by the stable and burgeoning development of Chinese economy, as well as the investment environment that has been consistently improved. Since the 1990s, transnational corporations’ investment in China has seen a rapid growth. Out of the “Fortune Top 500”, more than 400 have invested in China. When China officially joined the WTO in 2001, the competition in China, the largest and the last market in the world, also entered a new stage of development and a new scenario came into being. A series of changes have taken place in the investment strategy of the transnational corporations. Taking China into their global business network, the transnational corporations were all actively making strategy adjustments. They actively compete in the investment of China according to their own development laws combined with the new strategies and policies against the background of China’s entry into the WTO, and their experience and lessons they have gained in investing in China.