The aim of this research is to define the intensions and measures for obtaining the environmental leadership by the EU, and to examine its results and problems in the formation of international environmental regime s. The case here is the Copenhagen Conference on climate change in December 2009. The EU had been eager for winning the battle against climate change and the EU’s successful leadership, and developed domestic EU climate change policy first of all. The Conference, however, resulted in failure in terms of both the Earth and the EU. The one of the most serious obstacles in the process of Copenhagen was the state like China, India, Brazil and the US who emitted a large amount of GHG and opposed the legally binding agreement at the international level. Their attitude had never been changed by the EU unilateral commitment to reduce its greenhouse gas emissions to 20% below 1990 levels or financial fund proposal. The world map on climate change seemed to be different from the previous one. The EU was therefore required to make another strategy for environmental leadership in the new negotiation environment.