In this article the author examines the problems of interpretation and constitutionality of the Law of UkraineNo. 590-IX of 13.05.2020 "On Amendments to Legislative Acts of Ukraine to Improve Some Mechanisms for Banking Regulation" No. 590-IX, which entered into force on 23.05.2020.In the context of this, the author analyzed the provisions of this Law for its compliance with the Constitution of Ukraine and international law, in particular with the principle of legal certainty and inadmissibility of retroactive effect of the law in time. To this end, the author examines and analyzes a number of decisions of the Constitutional Court of Ukraine and the case law of the European Court of Human Rights.In particular, the author analyzed the provisions of the Law No. 590-IX for its compliance with Article 55 of the Con-stitution of Ukraine and Art. 13 of the Convention for the Protection of Human Rights and Fundamental Freedoms in terms of the right to effective judicial protection and restoration of violated rights. The author also examined the ter-minology, used in the Law No. 590-IX for its clarity, unambiguity and compliance with the principle of legal certainty.In this context, there were analyzed such decisions of the Constitutional Court of Ukraine as the decision of the Con-stitutional Court of Ukraine of 25 December 1997 in the case No. 9-zp, the decision of the Constitutional Court of Ukraine of 09.02.99 N 1-rp / 99, the decision of the Constitutional Court of Ukraine of April 5, 2001 No. 3-rp / 2001, decision of the Constitutional Court of Ukraine of January 26, 2011 No. 1-rp / 2011.In addition, this article considers and studies the practice of applying the rules of this law by the courts of Ukraine in the context of real legal relations.Based on the above, the author made a comprehensive analysis of this law, identified its shortcomings and proposed ways to eliminate them and suggestions for improving this law