The subject of the discussionis the problem of the rule of law, considered from the perspective of the European Union and the Republic of Poland, as a member state of this organization. The rule of law is considered to be one of the cornerstones of the functioning of the EU and individual Member States. Determining the content of this concept raises difficulties related to the lack of its legal definition. However, it may be helpful to refer to the findings of legal theory regarding the distinction between the formal and material understanding of this principle. At the level of the European Union, there is also a reference to other concepts that also describe the issue of compliance with the law by authorities. Not only acts of EU law, but also the case-law of the Court of Justice are important in determining the content of the concept of the rule of law. Similar problems also exist at national level. An additional source of controversy, however, is the different approach of the Polish authorities to the way of understanding the rule of law, and especially the qualification of actions of public authorities that are accused of violating this principle. The aim of the analysisis to determine the causes of such a state and to propose possible solutions to the problems resulting from it.