The topic of this paper is theorganization of the judiciary in the European Union. In order to describe the judiciary of the European Union in more detail, we will examine the historical development of the European Union itself, as well as its bodies and institutions. Special emphasis will be placed on the Court of Justice of the European Union, the main judicial body. The Court is a complex body that today consists of the European Court and the General Court. It was foundedin 1952, and its existence greatly helped the development of European integration. The treaties governing the court are: the Treaty on the European Union, the Treaty on the Functioning of the European Union, the Statute of the Court and the Rules of Procedure. The basic role of the courtis to ensure the application of European Union lawinthememberstates. The paper will also discuss the role of national courts in the application of European Union law. The role of national courts changes greatly with the country's entry into the European Union. National courts primarily apply domestic law, but if the domestic legal norm is contrary to European Union law, the national court will apply European law. It is also important to mention the principle of direct effect and supremacy of European Union law. The direct effectis a property of the legal norm of European Union law that warrants subjective rights for legal subjects, and these subjective rights are to be protected by the national courts of the member states. The principle of the supremacy of the law of the European Union tells us that the law of the European Union has priority over the domestic law of the member states. The development of the supremacy of European Union law has been made possible through two verdicts of the European Court: Van Gend and Loo sand Costa v. ENEL, which will also be the discussed in this paper.