The issue of the scope of application of substantive law norms by a tribunal of arbitration remains a relevant topic in Polish legal doctrine. Among legal scholars, there are still discrepancies in assessing to what extent an arbitral tribunal should apply substantive law. These uncertainties arise from the interpretation of Article 1194 of the Code of Civil Procedure and the manner in which the aforementioned legal norm is sanctioned. The answer to the research problem posed required an analysis of the public policy clause, the violation of which constitutes the basis for a complaint to set aside an arbitral award. The paper covers some basic principles of the legal order whose violation can result in the highest sanction for an award rendered by an arbitral tribunal – the setting-aside.