The dissertation is devoted to the solution of new scientific and applied problems of the implementation of international legal obligations on the rights and freedoms of convicts. A comprehensive analysis of theoretical and practical aspects of international legal regulation on the rights and freedoms of convicts at the universal and regional levels was carried out. The existing doctrinal basis of research is based mainly on scientific works on the theory of international law, European law in terms of ensuring human rights, mechanisms and procedures for their implementation and protection, determining the nature and essence of the implementation of international legal obligations, international standards, as well as on scientific developments on criminal executive law, criminal, constitutional, administrative law and process. The insufficiency of monographic and other studies on the actual implementation of international legal obligations on the rights and freedoms of convicts in Ukraine, guarantees of their implementation, and corresponding comparative legal studies was noted. On the basis of various criteria, the existing international standards on the rights and freedoms of convicts are classified: obligatory and recommendatory; universal and regional; regulatory and protective; general and special; depending on specific types of rights and freedoms etc. The author's concept of the European system for the protection of the rights and freedoms of convicts has been developed, which is a complex phenomenon based on the international system of protection of the rights and freedoms of convicts, implemented at the European level on a treaty and legal basis and with the institutional mechanisms. Thus, the key acts that form the treaty and legal basis of the studied system: the Convention for the Protection of Human Rights and Fundamental 20 Freedoms (1950), the European Prison Rules (2006, 2020), the Council of Europe Rules on Probation (2010), the European Code of Ethics for Prison Staff (2012); Guidelines for the recruitment, selection, education, professional training and professional development of employees of penitentiary institutions and probation, (2019). The role and importance of the institutions of the Council of Europe in ensuring the rights and freedoms of convicts (the Parliamentary Assembly, the Committee of Ministers, the European Court of Human Rights etc.), the activities of the European Committee for the Prevention of Torture and inhuman or degrading treatment or punishment, the European Committee on Crime Problems, the European Committee of Social Rights. Control, preventive, conventional, judicial and extrajudicial procedures for ensuring the rights and freedoms of convicts are highlighted. The conceptual and categorical apparatus of the research was formed, the author's positions regarding the interpretation of a number of categories were substantiated, namely: the international legal status of convicts, the mechanism for ensuring the rights and freedoms of convicts, the mechanism for implementing international legal obligations on the rights and freedoms of convicts in Ukraine; forms and methods of implementation of international legal obligations; principles of protection of the rights and freedoms of convicts, penitentiary system, penitentiary policy, European penitentiary policy, penitentiary security etc. The national model of implementation of international legal obligations on the rights and freedoms of convicts in Ukraine, its normative-legal, organizational-management, subject-functional and other components, is substantiated. Proposals and recommendations for improving the implementation of international legal obligations on the rights and freedoms of convicts in Ukraine in modern conditions, reforming the penitentiary system, ensuring the rights and freedoms of convicts, combating corruption, socializing convicts while serving their sentence, resocialization and reintegration after release are outlined, improvement of their legal culture, legal education and legal awareness, post-penitentiary assistance to convicts by probation authorities. It is appropriate to take into account the best foreign practices, in particular, the introduction of institutions of the Penitentiary ombudsman, penitentiary mediation, the expansion of forms of public control over the activities of institutions for the execution of punishments, during all components of the process of correction and resocialization of convicts, international and public monitoring, as well as selection, training and professional development of the personnel of the institutions of the penitentiary system, their digitalization, ensuring penitentiary security in the conditions of the legal regime of martial law, European and Euro-Atlantic integration of Ukraine.