The EU is an intergovernmental and supra-national organization that has the ambition to increasing their power by expanding membership to Eastern Europe, Central Europe and the Balkan countries. In fact, the expanding membership in the Balkan region has received positive support from prospective member countries in that area. The success of the EU in various fields such as economy and politics, is one of the reasons why many prospective member countries are volunteering and want to join the EU, one of them are Serbia. In the process, Serbia has to fulfill the criteria of Copenhagen as a condition of membership of the European Union by create transformation of political, economic and legal fields. Such as strengthen the democracy, entering into free trade agreements with neighboring countries such as CEFTA, EFTA, the European Union, Russia, Turkey, Kazakhstan, Belarus and the US to compete with free markets in the EU. Also, doing cooperation with the International Criminal Tribunal for the Former Yugoslavia (ICTY) to catch the war criminals in the past to improve the bad image of Serbia in the international world. Serbia succeed to get the status of candidate membership of the European Union on March 1, 2012 which became a new chapter for the Serbia itself.