The financial and economic system is inseparable from financial institutions. They enable the availability of the necessary financial resources to economic and other subjects, and are an important factor in the development of regional communities, such as the European Union. The European Union is an economic integration made up of 28 Member States, associated on a voluntary basis, which form a common single market. European Union Member States have transferred part of their sovereignty to the European institutions in order to make decisions in a joint, European interest. Fundamental European Union institutions are: Council of the European Union, the European Commission, European Parliament, the European Council and the European Court of Justice. Apart from them, there are many other bodies, agencies and committees. In the final paper, along with a brief overview of institutions important for the functioning of the European Union, the emphasis was made on financial institutions, such as the European Central Bank as the central institution of the monetary system of the European Union, the European Investment Bank, the European Investment Fund, the European Bank for Reconstruction and Development and European Funds Union. Although some of these are international financial institutions, such as the European Bank for Reconstruction and Development, and do not have the legal status of the institutions of the European Union, they are still an important part of the financial markets of the European Union. Financial institutions provide the realization of investment projects, and provide technical assistance and support to countries and companies in the European Union.