This graduation thesis describes the notion of The Court of Justice of the European Union, or precisely, its role in the legal order of the European Union. Considering its important role in a uniform interpretation of the rights of the European Union, all Member States analysis its organization, composition, jurisdiction and the procedure, due to the Court. The Court of Justice of the European Union, which has its seat in Luxembourg, consists of two courts: the Court of Justice and the General Court (created in 1988). The Civil Service Tribunal, established in 2004, ceased to operate on 1 September 2016 after its jurisdiction was transferred to the General Court in the context of the reform of the European Union’s judicial structure. Its mission has been to ensure the law is obeserved „in the interpretation and application“ of the Traeties. To enable it properly to fulfil its task, the Court has been given clearly defined jurisdiction, which it exercises on references for preliminary rulings and in various categories of proceedings. Also, in this graduation thesis are represented examples of actions for annulment of European Union acts, actions against the European Union for compensation of damages, procedure for giving opinions, etc.