Abstract: In the context of global systematic governance， the constructive interaction between transnational corporate operation and international law has become a global focus. In choosing the form of regulatory governance，the“hard law”has a legal binding power but high in“sovereignty cost”and liableto be rigidified；the“soft law，”though lacking constraint，can give a country more space for independent choice，low in the cost for negotiation and amendment and more adaptable to global changes. The boundary between the two，originally not clear-cut，tends to be blurred in the development process of global rule of law. They should supplement each other to jointly regulate the business behavior of transnational corporations. In terms of the soft law，from The UN Code of Conduct for Transnational Corporations（Draft）to the“global compact”of Guiding Principles，the concept of corporate social responsibility has been gradually integrated into the soft law governance；and the regulation on transnational corporations’business conduct has developed from a general concept to specific environmental and human rights protection responsibilities. In terms of the hard law，the negotiation of transnational corporations on human rights protection compact has to overcome manifold disputes including human rights standards，with the process long and difficult. Yet，the attitudes of various countries in the resolutions of human rights institutions，their implementation of such soft laws as the Guiding Principles in domestic laws，and the “Investor’s Social Responsibility Clauses，”which is a soft law established according to soft law standards，all reflect that the norm that transnational corporations should shoulder up their social responsibility is developing into a customary international law. In the UN system， the governance of multinational corporations should exploit the advantages of both the soft and hard laws；and，in combination with the practice of global systematic governance，promote the construction of an orderly world that respects human dignity and lives harmoniously with nature.

Key words: transnational corporation, the UN, global governance, international law, corporate social responsibility