【摘要】：Environmental and ecological issues related to the survival of humanity. In a period of high growth of ecological globalization, environmental pollution and ecological damage are very serious and environmental conditions are deteriorating. In the context of rapid development of global economics and the wide gap of countries, International Environmental Law arises on the base of profound understanding to environment and environmental problems. The solutions to environmental problems which generally have globalization also require all countries to participate. However, there are profound differences for countries in economic, political and other sides, so that they could not enter to the same system platform from different physical space. Therefore, in order to accelerate international cooperation, differential treatment is into International Environmental Law from the beginning.
As a legal and politic tool to re-distribute the benefits, differential treatment achieves the fair of world trading system, which products、develops and improves by the evolution of International Law. Differential treatment is an indispensable part of International Environmental Law, which existence has legitimacy and rationality. The principle of social justice asks to give "the least beneficiaries of the biggest interest" in different economic and social condition which is in order to ensure the sharing of global resource, but economic externalities which is the key cause of environmental pollution needs a system to regulate. Furthermore, the game of economic and environmental benefits between the developing countries and developed countries needs a system to guide both sides to get the best interest. Differential treatment meets these requirements.
With the development of global environment, differential treatment in International Environmental Law is not only the face of severe external challenges, such as the definition of the objects of differential treatment in the system of climate change, but also a "soft law" which has some weak and ineffective. The implementation of differential treatment needs the sovereign countries to tradition or give up some sovereignty, which will have an impact on the sovereign countries. However, we can not deny that differential treatment promote international environmental justice and protect the common interest of mankind. As a kind of embedded implementation mechanism of international environmental justice, the design and improvement of differential treatment relate the development of International Environmental Law. The equitable sharing of international environmental responsibilities directly affects countries, especially the basic rights of the developing countries. Therefore, the ecological mechanism of differential treatment based on justice, the build of international environmental cooperation mechanism to play the function of countries and the build of international protection mechanism to improve global sustainable development, which it is the most important to play the function of differential treatment in International Environmental Law and to protect the global ecosystem.